Yeah, I'll change up the cons and counters sections (even if Bulk Up is stupid and you should never use it on Medicham...)
It may be dumb on Mega Medicham but then you ask why Bulk Up on Talonflame is so popular? And besides when your effective base attack stat is 248 having anything to boost your attack is gonna make you hit hella hard.
When Medicham's High Jump Kick gets priority, then you can come talk to me.
What does priority on BB have to do with using Bulk Up over SD? As far as I can see, SD would be better since you don't have to worry about getting hit due to the priority.
mkTalonflame can use Bulk Up because it's typing is actually good defensively and it has priority Brave Bird to bypass Speed tiers, letting it invest in bulk. Bulk Up on Medicham is a waste, since it is a wallbreaker and a cleaner. It misses the coverage you take away by adding Bulk Up, and still gets KOed by faster threats. So no, no Bulk Up set.