If an engine uses oil, can you change it less often?

Oh, I agree that it’s not going to remove contaminants, but it’s going to disperse them thru the total quantity of the fluid. The question is, is the total quantity of contaminants an acceptable amount when you change the fluid. May or may not be, depending on how ‘many’ of those contaminants are being burnt off.

The only answer is ‘will vary, depending on your particular case’.