I haven't read through the nuts/bolts of the legislation but I'll give it a shot on my understanding as a semi-insider in the industry...
the 100k homestead exemption is just an increase on the current homestead exemption that applies to the overall ISD rate for homestead properties. The 10% annual cap on assessed value across all assessment offices (city/county/isd etc) is still in play.
the 20% cap on non homestead property is a doozy, no idea why they chose 3 year timeframe on it and no idea how it will work in practice with the gory details. in theory it appears that if your (non homestead) goes up more than 20% in one year, the increase in value will be capped at 20%. I would assume it will be similar to homestead cap where the assessed value will just play catchup the following year even if the market value is flat. i guess this is a good thing as it prevents small biz from getting totally effed by a rogue value increase, but caps across the board are a terrible idea with our system.
as for the ISD funding, there isn't any actual lost revenue to the ISD's the state is just filling the void from the rate compression (ignore the fact schools are grossly underfunded in general). it's essentially the state stepping in to cut a check to make ISD's whole. the BIG issue with this is it's set to expire in 2025 and we damn well won't have another $30bn in surplus to cover this check again, so what happens then, i have no effing idea. but in typical government style we'll just worry about that then - or as the GOP will probably do, just have ISD's slash their budgets.
renters are the losers here of course. The dems tried a Hail Mary with their plan but it had no shot in hell. Their plan of having renters report their paid rent to the state would require such an insane amount of administration that it’s hard to imagine working.