I was quite excited for Datastart until I saw that they keep a good chunk of the functionality behind a proprietary license [1]. It's not even about the price (it is a bit steep though, but I guess if you use it in a commercial project it will pay for itself), it's the proprietary part.
A "good chunk of functionality" is a mischaracterisation. I don't use anything from pro and I use datastar at work. I do believe in making open source maintainable though so bought the license.
The pro stuff is mostly a collection of foot guns you shouldn't use and are a support burden for the core team. In some niche corporate context they are useful. You can also implement your own plugins with the same functionality if you want it's just going to cost you time in instead of money.
I find devs complaining about paying for things never gets old. A one off life time license? How scandalous! Sustainable open source? Disgusting. Oh a proprietary AI model that is built on others work without their concent and steals my data? Only 100$ a month? Take my money!
It's not about the money, it's about the fact that I would depend on vendor-locked functionality. I cannot maintain my own fork of it if for whatever reason I had to. I don't want to fork datastar if I don't have to, but I want to be able to do so if I have to.
Alpine does have a "pro" version as well, but it's just copy&paste code examples. I am not complaining about Alpine, and I even got my employer to pay the maintainer more than what the datastart guys are charging for their pro version. So again, this is not about money.
You get the entire source with pro. Nothing is stopping you maintaining your own private fork for use in your commercial product. If datastar the non profit disappear tomorrow you would still have the source. So where is the problem?
[1] https://data-star.dev/reference/datastar_pro