upnorthjoe,
absolutely, i would gladly take medicare earlier if possible, having paid non-subsidized healthcare since FIRE.
but concerns about any\all of these stealth taxes are magnified because there is so much attraction for gop grift & cronyism.

neither party much wants to touch the 'headline' personal (zero business mix) tax brackets.
but many stealth taxes have a history of getting passed without much worry that enough of the public understands them.
and, scarily, these can have (and some do) have nonlinear thresholds with big leaps, all precedents for more such.

partial list :
irmaa
investment tax
AMT

on the other side, pretty much all significant deductions have become near zero (thus already at a floor) , other than the standard deduction.
so concerns over deductions becomes secondary to retrospective changes to roth and\or IRA and\or nonqualified plans.
and dropping the inheritance tax limit to <$1m in the boomer demise era would reap trillions for a decade plus. (hooray! more for ICE and supercarrier strikes on fishermen)

i guess there is some safety in that trump cant do much here via tweet and EO, but he is not above trying such. my guess is there would need to be an angle that further boosts crypto scams that the gop continue to support as a whole. (e.g., lower tax due for IRA holding crypto assets converted to roth)