In the 'old days' prior to furling genoas a sailor would forever be switching headsails: Genoa No1, 2 and 3, Jib, Storm Jib. So you had to whip the sheets off fast, and on fast!
Bowline is great for that.
In the modern world of cruising the bowline is undone off the Genny about once per year if lucky. So it does tighten up and become a pain to get off.
However I still use them because I think its best to keep the number of knots used on a boat to a bare (bear?) minimum. Otherwise the big furry thing can bite ya on the bum in the middle of the night.
Some folks have started using a single line for their sheets with some knot forming a loop through the clew. But this ain't such a good idea because if the sheet breaks you can't tack and have one good sheet remaining. You have a sail flapping and when furled the clew is too high to thread a new sheet! (Sheets break most often at the knot, of course cos it 50% or 60% strength as you've pointed out)
So I keep bowlines, and I keep few as possable knots used on board.
Just as an aside: When sending someone up the mast professional pullers... actually 'pullees' are told to use a snap shackle instead of a bowline. This sends shivers up my spinless as a snap shackle can unsnap! But Occupational Health and Safety mobs want to know the breaking and safe working loads and they can work that out with a snap shackle but NOT with a knot. Of course you can put in both and have a safety line too.