The gtx 5 10 doesn’t feel flimsy to me- it’s a pretty clumpy thing, definitely not my favourite sole but it does work well. Best “bike specific” winter flat shoe I’ve worn, but that’s not an especially high bar tbf.
My favourite bad conditions shoes are Columbia Fairbanks Omnis- they don’t have a “sock” to keep water out so for best results you do need to wear trousers so that water doesn’t get in the top, but they’re otherwise proper waterproof, super warm, and stay warmer than most when wet. And bizarrely they feel better on the bike than most bike-specific shoes, while at the same time not being very good winter walking shoes which is what they’re designed for (because they lack squishy mud grip while walking). Obviously shoe feel is very subjective though.