The Lexus is operated in an environment where the average winter temperature is -10 F.
The Yugo is operated in the same environment.
Both will benefit from the better low pour performance of synthetic oil. But that's not the point. If you toast the engine the Lexus you take a bigger financial bath than the same problem in a Yugo.
You are correct. "Both will benefit from the better low pour performance of synthetic oil."
THAT is exactly the point.
If I toast the engine in the Lexus, it would likely cost more than replacing the engine in the Yugo.
But remember - I can't afford the Lexus. I can only afford the Yugo. So, to protect my investment in my precious Yugo, I will still adopt the best maintenance practices, use the best oil, etc. - because the Yugo is the best I can afford. Just because the Yugo costs less and costs less to replace is no reason to skimp on maintenance or maintenance materials.
The cost to replace the Yugo might be proportionally greater for a person of my income and means than for replacement of the Lexus that others could afford.
It really boils down to what another previous poster said (paraphrase): If you take care of your tools (or cars, boats, planes, etc.), you will almost certainly be rewarded with better life and performance.
Dargo implied- no, wait - he said - that if you don't have the best equipment, then you shouldn't use the best oil. Obviously, "best" is a very subjective term. Again - that is the flawed logic. Even if you don't have the best equipment, it can still benefit from the best oil, regardless of it's initial cost or cost of replacement.
Even you admitted that both a Yugo and Lexus would benefit from the use of your preferred oil. Or whatever.
Take care.