I agree with your assessment. ERC-20ish experiments are great for rapid prototyping.
For this to work at all, the KYC/AML token infrastructure must build an ecosystem for KYC transitivity so that investors don’t have to send their information to everyone, or even worse sending their information to everyone for every token (whitelisting in a smart contract).
If the ecosystem does not develop, then the liquidity for any given token will likely be too low. This prevents the “liquidity premium” which gives additional value to an asset because it can be easily bought or sold at a moments notice. This is currently seen as the delta between pre-ipo and post-ipo pricing.
Ravencoin is working on a potential solution to this problem.
Whether Ravencoin becomes the defacto standard for STOs, or whether it just increases awareness of the limitations of the current experiments and pushes the industry to be more innovative remains to be seen.