Assuming there's no scamdemic similar to Covid between now and 2030, you can continue to exit the country every 90 days without a reporting requirement.
Yes. Even now, most land borders require a TM6 to be filled out on paper. If it becomes mandatory to do one online on May 1, then unfortunately, even air arrivals will be affected. In fact, I suspect like Cambodia, they'll implement the online TM6 requirement for air arrivals first then for land ones later.