I’ve reduced the install size by getting rid of all the stuff I don’t use or have finished (training, landing challenges, bush flights, liveries). My installed content sits at 189 vs 272 not installed.
It still takes over a minute for anything to happen at all after pressing play in Steam. Then a long wait checking for updates, At the 2 minute mark it starts loading. (this time)
It accesses all the installed content so reducing install size helps. Anyway the actual loading (reading stuff from disk) part takes 1:40, with the dilly dallying phase before loading it is indeed 3 minutes 40 seconds.