You would think that the amount of deliberation owners spend on choosing motor oil that they were calculating what it takes to get a satellite into orbit. Maybe it is one of the few things that an owner can attend to and not get in over their heads. I wonder if brake fluid gets as much attention. How many owners on this forum have cars that are overdue for time and/or mileage. I recently polled nearly all my friends on that and got a unanimous, “Huh?” Check your manual. And by the way, don’t confuse the DOT types; like synthetic motor oil, there are various blends for different applications. My Sprinter’s turbo-diesel requires a very specific oil formulation for low ash, sulfur and volatility to protect the DPF and SCR. The only readily available and reasonably priced oil that meets the MB 229.51 or 229.52 specification is Valvoline Synpower MST. With 13+ quarts for a fill, that gets expensive and if you let the shop do it, grab your socks. Comparing Valvoline to the next popular choice, Mobile One, the spec sheet reveals some only minor differences, but both exceed Mercedes-Benz specifications. The oil required for the Subaru FA 2.0 engine is available from a wider variety of suppliers. Last time I used Mobile One because I was at Costco, the price was good... done. I did use an oil filter acquired from the Subaru shop. This same sort of discussion about the best oil filter never ends. Done.
Yet another explanation of oil types:
https://auto.howstuffworks.com/synthetic-motor-oil2.htm