The new pronunciations seem conventional enough now, although "offen/often" can go either way, and I can't say I've ever heard anyone pronounce "tortoise" in a newer way. Is it supposed to sound like the end of "turquoise?"
Yes, though some speakers use an S rather than a Z sound (think "choice").
I have only heard these pronunciations from British speakers.
I look forward to hearing that from Zoomer college students any time soon then.