Sometimes I feel pride as a craftsman and then I see what some anonymous noone made just to hold somebody's nasty fucking tobacco snorting powder 250 years ago and am reminded that I ain't shit
I really don't think this is a fair assessment of your skill. You're working with a different media, which doesn't have the effects that mother of pearl has. You don't have the proper cutting tools to make such edge forms, and on top of that, would you be able to blend the plastics you work with to make such a box?
Like, your boxes are good, but they're a completely different beast. You didn't even get to reach your full potential bc your job pulled you to do other tasks that take you away from your craft.
The stuff you make has a real neat geometrical feel to them that I appreciate and I'm sure others would too.
Comparison is the killer of happiness... as they say.