I do standing efforts every now and then, but I'm not massively strong or heavy. Wahoo kickr weighting a tonne does help, got far more problems with "dumb" cheap turbo
Standing up isn't the issue. I can stand up and ride at 100W or 500W basically steady. It's doing proper sprints that are going to be unkind to frames and turbos.
Yeah, do your QRs up properly.
I'd probably add don't do sprint training on turbos but that's me. I'd have broken way more frames if I was sprinting on the turbo.