My main issue is that the default buttons start at 30%. I usually tip between 10-30% depending on service. With somewhere between 18-20% being standard.

10% be like, you didn't really do a great job but I know they're not paying you enough

15% is like, you did your job and didn't screw up in any major way, but there was nothing notable about the experience.

Around 20% being more like, you did good, thanks!

And 30% is basically for being a mind reader that can predict my every need before I have it. Things like coming by with refills before ours are empty (for things with free refills), getting condiments ready/at the table either before, or while my food arrives, etc. Along with all the "expected" kindnesses and whatnot.

Unless my experience was genuinely negative, i pretty much always leave a tip.

50% is nuts. 30% as a minimum raises a lot of concerns for me, like the person programming the payment system is somehow getting a cut.