In some ways synthetic is like an iPhone you don't really need. IPhone 8,9,10,+, etc. but since race car drivers are using it, so should you.
I've had or still have cars over 400K, 370K, 200K+ miles all on dino ...
None of my Owner's manual ever specified synthetic.
If you are not racing or redlining the engine and not doing extended oci, dino will work.
The only reason I use syn in couple of our cars is to extend the oci ... Don't like to change oil when it's raining all the time