Picard was still a golem in the "alternate" universe from S2, was said in Ep 1
The current Picard is a copy, a near perfect copy, but still a copy. There was a big snafu with Mem Alpha that listed him as dead ( Still does) but unlike now, had a new entry with Picard (Golem) Now there just combined.
Goes back to the transporter, does it destroy the original, and make a copy somewhere else ( Like what an actual transporter if it existed would do) or is it the same person just reasembled.
Don't forget Grey from Discovery, They are in a body, but the original died, and the new one just has memories copied from the symbiote to the new golem.
Spock on the other hand did die ( a quite grusum painfull death) but his original body was "reset"? just his memories were restored.
As for Q, I kind of wish he finger clicked picard back to life. Becauase at that point, he was just talking to the copy, just like data's memories in Season 1
I don't think it was a SNAFU, I think it was just the braintrust at MA wanting to dictate their particular view of Trek and resistance to the new trend.
Thankfully I think pressure forced them to not be..themselves over it.
But keep in mind Star Trek is about exploring what it is to be alive, what is human, etc. The question of "Is conciousness more than memories" and "What is a soul?" has been going on for a long time.
Its clear that whatever unquantifiable, unknowable, whatever it is..a soul, spirit, divine energy, whatever...did make the transition from Picards original body to his new Synth body.