Do you belong more to souce first or to speakers first school of thought ?

Clearly any speaker will have the greatest impact on overall sound quality and it’s also the source of greatest distortion. All other components deliver significantly less distortion.  To get the best out of a high end speaker will require better electronics especially source components. The correct balance is impossible to determine precisely. Ultimately it’s a function of what you can afford and trial and error is your only guide.

Recordings also often have a lot of distortion.

we are talking about excellent or better source and similar level speakers.

what's excellent/better? How do you define it? By a threshold of what?

speakers add the most distortion and coloration so you have to start with speakers you like the sound of that fit your room. All this crap about the guy from Naim declaring source first is just that,,,, crap from a guy who sold sources...

Put a $1000 all in one streamer/integrated amp with $100,000 speakers.

Then put a $100,000 front end with some $1000 speakers.

I can guarantee you which one will sound better.

Neither will sound good. Spend $30000 on speakers and $70000 on the rest.  Front end is more important.