Stain just doesn’t penetrate white oak all that well. The other downside is how often you will need to apply stain to keep it up. Vertical with protection from weather like overhanging roof it will last long enough with nothing done to outlast you in my experience. My grandfathers family barn was built when he was 8 with white oak, red oak, and has chestnut beams from a even older barn that blew down in a storm. Per my grandfather the beams were cut by his great grandfather. It’s unbelievable how well it has held up over the years. May need some work in next 10-15 years though. Never had new siding other than the occasional piece
He’s 85 now btw
