These burner phone numbers not exclusively used by criminals, a privacy-minded person would use those to make accounts on services that require a phone number (and sadly, it feels like there's a lot of these lately)
If you look at these companies it's never aimed at the privacy enthusiast use case. They are aiming for mass-sms outreach, anti-bot measures and sell them in bundles of 1000s.
Instead of requiring a phone number, accept a small amount ($1-2) in cryptocurrency. You can charge extra if the user sends too many DMs or gives too many likes. Perfect solution against spammers.
However, personal information costs much more than $2, so the companies will continue to demand a phone number. Mobile OS developers even developed a format for automatically transferring SMS OTP to a website to help scammy companies.