so I figured it wasn't clear from rules (how did I miss that) and apparently people took different approach on what's going on with timer at the end of a game.
Answer is - Timer stops NOT after last boss is dead, but AFTER you lose control after last boss (UNLESS it happeneds at the same moment, like in BFE).
I don't see any reason to stop it earlier since game is still going and ingame timer still counts that standing time until cutscene starts.
I now will go over all runs on lbs checking endings.
For single-segment runs it doesn't matter cause they just check IGT and are good to go (so if you bring arguement, like Dylaneka's Normal TFE it won't matter, cause it is single-segment run). I will double-check that final RTA is still calculated the same way over all runs.
Old games have "Playing time" which is somewhat like "IGT without loads", but I'd rather not use that field, and you have load removal tool for most of SS games now, just check inside your livesplit.
I bring this on forum, cause not every runner is on discord.
I'll add timing line on Rules for every game mentioned in header of this topic.
Discussion here will be closed, please come to discord if you want to talk about it.