I completely agree with you but it's surprising that the biggest factors aren't being brought up.
Most people won't pay for a ton of small services since it adds up. There is a minimal threshold to pass to make online transactions financially reasonable, making the pricing models make little sense for most services. Given that most cheap services (ie. those at or below $5/mo) don't have large infrastructure costs, it's an even harder sell. Not to mention that sometimes people rather watch movies or television than get tools to make them more productive.
This is doubly compounded when you look at opportunity costs. With the amount of software that can be self hosted, the costs isn't just the comparison of having the tool or not or even other developer focused offerings, but instead having this tool (or access to it) versus any other tool that can be self-hosted (including those that might not exist yet).
Also, lets say we spend $5/mo, well for that we can host our own server which can easily be used for more than one purpose (with WireGuard now even the smallest VPS can be used to saturate most home links and bypass CGNAT easily). Increasing the monthly spending just increases the amount of opportunities.
This of course doesn't touch the elephant in the room which is privacy.
For the regular user privacy isn't a huge deal for these small services. For the average reasonable user that doesn't upload sensitive data, at worst it would be something like a personal photo being seen.
On the other hand as a software developers using these tools is a lot more complicated. Licensing, copyright, and possible work contracts start to matter. If the service interfaces with code (like Kite or GitHub Co-pilot) then you get into a some serious murkiness due to the fact that you don't really know what they are doing with it on their end. Even the things like telemetry and what type of data is being sent back matter in corporate environments.