Tradition is an enormous hurdle to overcome despite the fact that there are newer and easier ways (take for example the metric system in the United States).  Big change is slow and can take generations.  Traditional sheet music notation has slowly evolved with small incremental changes over centuries.  But there have been no major overhauls to address what many believe are significant challenges to beginning students of music. 

It’s important to remember that the alternative notation movement is not about changing the music itself nor music theory.  It’s about simplifying the reading of music to make learning and playing more efficient.  As a result, more people will want to participate in the joys of playing music, perhaps for a lifetime.  And in the end, does the listener know or care what sheet music notation musicians are using?  Sheet music notation is just a musician's tool.  I believe there is plenty of room in the toolbox for new and better tools.

However, to be accepted, an alternative notation must convince the music world that it is worth using something different.  Unfortunately, the gatekeepers to music instruction have a lifelong dedication to traditional notation.  It's what they know, it's what they teach, it's a part of their livelihood. It will take a lot of convincing to win music instructors over to even look at an alternative notation much less actually teach it. 

The good news is that it has been done, at least on a region basis.  Klavarskribo was convincing enough that it was adopted by the Netherlands' public schools.  But that was then, and that was there.  Now in the US, it is going to be hard to make a case because most readers of traditional notation have an immediate negative response to the idea of an alternative, often without even looking it.  

In my own experience with friends, family, and acquaintances when talking about alternatives, I have gotten rather abrupt and dismissive reactions.  I have also observed online discussions of alternative notations with comments that represent the view that those who cannot read traditional notation are stupid and/or lazy.  “People who think it's difficult were probably taught badly, or couldn't be bothered to work at it, or are a bit dim.”  That is an actual comment on an online video about alternative notations.

There may also be an “initiation” syndrome in effect which I summarize as: “I suffered through the initiation into this club and so by golly all new members are going to have to go through it too!”  Musicians brought up on traditional notation, even if they may have struggled to learn it, are now in the club.  And many of the club members do not want to make it easier to join by breaking club tradition.  Here’s an actual response to a comment I found online by a student struggling to read music: "I spent half a lifetime struggling with the old system, AND SO SHALL YOU!!!"  See even more real comments found online below.

However, if music instructors can be convinced that an alternative provides a more effective, enjoyable, and efficient learning experience, then perhaps they will realize that they can attract and retain more students. And hopefully, that will provide an incentive to consider breaking tradition. But they are not going to adopt alternatives without some persuasive evidence of their value.  And this is where academic research comes in.

More actual online comments 

"I get mad when people balk at how much work it takes to learn to read sheet music or play an instrument. Of course it takes work! Everything else does, too!"

"[Traditional notation] is easily accessible to anyone willing to let go of the preconditioned idea that note reading is too hard to learn. Far from being difficult, standard notation is the easiest thing under the sun and trying to replace it for lazy people and come up with over complicated substitutes is a complete waste of time."

"The challenges can be solved by tightening those bootstraps and doing something called learning."

"I spent half a lifetime struggling with the old system, AND SO SHALL YOU!!!"

"If you are an amateur, you can make up colors and symbols, but just learn to read music instead of being lazy."

"Conventional music notation is logical and is very easy to learn. People who think it's difficult were probably taught badly, or couldn't be bothered to work at it, or are a bit dim. I think it's a mistake to fix something which ain't broken just because a few dim people are dim."

"With all these new notation systems... it really comes to the conclusion that music is not for everyone! "

"it is what it is. it's what i've been reading for more than 40 years. leave it alone."

"I strongly believe that music notation is the most effective and efficient way to write, read, and analyze music. It has been developed through centuries of musical evolution and the contribution of numerous musical geniuses. In my opinion, it is not worth exploring other alternatives as it is the best compromise possible."

But then on the other hand there are interspersed plaintive comments like these:

[Traditional notation] "is inherently hard to learn. I feel like there HAS to be a better system than what current music notation offers, but I can't find it."

"I’ve played piano since I was seven years old, and while I’m quite used to sheet music notation, I still feel like a moron when sight reading something cold. Maybe I’m not alone."

"I play pedal steel guitar. I can read legit western music, but rarely do because TAB is most effective for this instrument."

"Notation was precisely why I gave up on any instrument as a kid because every time I had a motivation to learn, I was told that I had to learn the notation first, and then I could learn how to play. As a grown-up, I finally found a teacher who taught me how to play first and then to understand what I was playing by looking at notation."