Fully Tagged PDF (even for math) is in the works for LaTeX

Using overleaf has a unique advantage when you have a group of collaborators that use different OSs and have installed LaTeX using different approaches (e.g. one on Windows with MikTeX, another one on Linux with TeXLive, another one on Linux with distribution provided packages). It gives you a platforms that can be used as a reference: if the doc compiles fine there and it does not compile fine for a subset of the collaborators, it is easy to convince them that the issue is on their side.

A pain point is that the free tier is insufficient even for the simplest document with the LuaLaTeX engine.