Nuno Santos is presently a better coach than Mourinho and certainly LvG, yes.
This is beside the point though - do you doubt that he is certainly a better manager than OGS?
Do you also disagree that Silva has achieved more in the PL than OGS?
Ole has worked in PL for 4 months at United with very good results and previously at Cardiff for 5 months with bad results (and a bad team).
Nuno has worked in PL for 32 games, very small sample size and he has not really achieved all that much. They are 8th and 1 point above 10th which considering the lack of quality in the bottom half of the league and their investment is probably the right spot to be in.
Silva has been there much longer than either with mixed results at all clubs he’s been at. He was also relegated with Hull (like Ole with Cardiff) yet he doesn’t get half the stick for it. His end to Watford spell was bad, basically aside from their first 7-8 games they were nothing special and he was sacked in January. His results at Everton have been below expectations too. I don’t really get what he ‘achieved’ in PL that puts him so far above Ole in your eyes. His biggest achievement was starting the season well with Watford
I don’t see how from each of their careers you could draw enough conclusions to be so firm about one being much superior than another, unless you are blinded by liking one and disliking the other, which is clearly the case for your bias here.
If you judge them purely on the most recent time (this season) then Ole has done better than either of them so far, of course. Unless the sample size you want to use has to be the last two or three games, which seems to be what you are trying to use here.