While most of the problems with this will probably shake out as the new rules are defined, the thing most concerning me at the moment is this bit in the op:
“ Iam not sure if it should be under immigration and visa but my experience tells me that immigration will ask for tax documents in the future.”
Though I can’t see the point of them asking for tax docs (that would be an issue for RD) it would make sense for them to require a TIN to be declared as proof you are registered for tax here if you have stayed more that 180 days in a tax year. From April 2025 they will obviously be able to see this on immigration system and a fairly simple link or check with RD would identify if a tax return had been received giving the option of immigration either insisting one is done or an explanation of why one is not required - simplification would suggest they just hand this off to RD.
Essentially this would mean everyone on one year extensions would need to do a tax return.