Remove steaks from refrigerator 30 minutes before cooking to reach room temperature.
Pat completely dry with paper towels; lightly brush both sides with oil.
Mix salt, pepper, garlic powder, and onion powder in a small bowl; season steaks generously on both sides.
Heat cast-iron skillet over high about 5 minutes until smoking hot.
Cook steaks without moving 4-5 minutes until deeply crusted.
Flip; cook another 4-5 minutes for medium-rare or to desired doneness.
Add butter and thyme; tilt skillet and spoon melted butter over steaks 1 minute.
Remove to cutting board; rest 5-10 minutes before serving.
Serve drizzled with pan butter.