In our version of beef Stroganoff, the beef is cooked as a whole steak to maintain a more tender, medium-rare center, while the sauce is carefully layered to optimize its flavor.
Just because Lemmy seems to be obsessed right now, but it's also a legitimately delicious dish, and Kenji is the man.
I've made mushroom stroganoff before. It's not the same as beef, but still very tasty. Just bump up the amount of mushrooms you use and throw in some meatier varieties like shiitake, oyster, chicken of the woods, lions mane, etc.
Especially tenderloin. You could use chuck instead - you'd want to tenderize it and/or braise it for a while to make it more tender prior to adding it to the recipe. I'd honestly use chuck instead, since it has more flavor.