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

@hilde45 and others.  I appreciate your humor.  Let's not be REAL serious about this.  Most us us have a decent to awesome rig.  For those in that category, it is upgrading the weakest piece.

That's certainly true, generally speaking, but first it is not always easy to determine the weakest link, and then by changing any component your change the overall balance, so you might upgrade but not get better sound or improve some aspects of the sound and make others worse. This is a form of art, I would say.

In my case, I think I know that the weakest links are cartridge and speakers, though they are not weak links, so I have no need to upgrade, only a moderate wish.

There is theory and there is practicality. Linn's theory is correct, but to maximize your investment, you'd want a well matched system. There's no point in arguing for a $1000 front end and $100K speakers or vice versa. So much is based on the room.

That's the advantage of any great source component - it will work just fine in any room where there is enough space to put it in. You always have to deal with resonance control, though.

After 50 years in this hobby I’ve settled on the following hierarchy:
Amplifier
Source
Speakers
Cables
Room acoustics...