Ugh. I remember how much Tailwind Labs has struggled for funding and it sucks to see Shopify get them. It also sucks to see they're discontinuing their paid products permanently, effective immediately -- they're not making them free, they're taking them away. You simply can't get them now. I understand why this had to happen but it is sad to see.
Usually when stuff like this happens, it means that Tailwind's developers are moving to work on Shopify instead, which means Tailwind CSS itself goes into maintenance mode. That's what usually happens when a dependency is picked up by a company with a huge, "more interesting" product -- the dependency starts to depend on the more interesting product for attention, and stops receiving attention on its own merits. It grows only to support the more interesting product.
Furthermore, I already have specific experience with Tailwind Labs neglecting their other libraries that aren't Tailwind CSS itself, probably because they were only meant to support their paid products (which now will no longer exist! so maybe those other libraries will just stop getting updates altogether). Headless UI was something I wanted to rely on heavily, but it's not built to be flexible enough and basic issues from 2021 or earlier haven't been resolved or seemingly even reviewed.
Now that they have Shopify, I'll be surprised if Tailwind CSS continues to receive any more attention than Headless UI did all those years ago. This acquisition puts Tailwind CSS in exactly that position.
