I spent time looking into this a couple years ago as a startup founder with this problem. We are in the finance space so I saw how bad the treasury options were with our bank, given their fee cut versus plain T-bonds at the time. I looked into which brokerages allowed us to setup self-directed accounts (many banks don't offer that for businesses at all). I found the "correct" approach. But then there would be more paperwork and back and forth to set up that new account, then manage transferring money around when we needed it, logging into a different system. On a ski trip a friend in finance told me "you're being dumb, if your bank offers you a treasury plan with a one click button, even if it's not perfect, click that button now!" So I did.
Then, the benefit of saving 1-2% extra versus spending my time trying to actually running the business and doing things with our money in the real world, has meant I have never looked back. 1-2% on millions of dollars is significant but it's not nearly as impactful as finding Product-Market-Fit in your actual business.
All this to say: I'd be in your target market but I'm simply not interested in a "marginally better" treasury system versus just going with my bank's options that make it easy for me.