I’m 6’3 with a 32 inch waist. Tall skinny, perfectly normal, but finding kit that fits well is tricky. Trousers are the most tricky – the assumption that big waist equals long legs is frankly ridiculous
Montane do long leg cuts but they also vary them in length based on waist size. However, Montane Terras can be cinched up nicely so I have a pair of XLs that fit OK
Haglofs stuff fits nicely – Rugged Mountain Pants in a long leg. But they’re outrageously expensive!
In general have a look at Scandinavian brands. They tend to be cut to fit the typical Scandinavian man who is tall and slim. They won’t be cheap though. Fjallraven have a good range and also sell trousers with an unfinished hem
Rab also do some trousers in long leg length, as do Prana
I found a company that would make outdoorsy trousers to measure that wasn’t very expensive, but I didn’t buy anything from them for two reasons:1
1- i’m not an abnormal size so buying made to measure felt wrong on principle
2- their materials were unproven so was looking for something I could trust