Seems like it might be a bit of a minority opinion, but I think that a good number of investors stay away from crypto not because of technical issues but because of valuation. None of the traditional metrics of valuing stocks, bonds, currencies, or commodities seem to be able to yield any insight into Bitcoin or crypto price movements.
I agree that issues of buying, selling, and holding cryptocurrencies are problems and can be quite confusing at first. But at the same time, these are easily solvable problems and are to a large extent already being solved with more reputable service providers and better UIs. On the other hand, I see very little progress being made in accurately valuing cryptocurrenies.