This is a really interesting thing to think about.
The example in a follow up tweet was Gini Wijnaldum turning out better than Gylfi Sigurdsson.
I think that this while true also highlights what we can gather from statistics and using critical thinking for how their role will change in the new team.
Wijnaldum at Newcastle looked to be a talented (if I remember right without too much hindsight coloring things) but still rough player. One of things that really struck me at the time of his original transfer to Newcastle was that he was rated as a HUGE prospect by Goal Impact. For Newcastle he was a regular player (3169 minutes played) but not one that stood out in any particular way, especially in the end of season awards or team of the season.
Sigurdsson on the other hand, was THE GUY for Swansea. Where just about everything went through him on that team. What I think that we can learn from this is that for high usage players the statistics that they produce can be inflated and might not directly reflect what the players would produce on a different team. Moving to Everton, Sigurdsson has not been nearly as central to everything that would happen with the team. It also hasn't helped that the manager has changed often and the style of play has changed quite a bit.
I think one of the things that I would take away from the way that Liverpool built their team is that really thinking through how a player will be asked to play and what role they will fill on the team is easily the most important question to ask. This also meshes well with Jurgen Klopp's ability to maximize the tactical system that he implements to the squads strengths.
One of the other things that I think that I have come to be convinced by is that the distribution of talent is much flatter (outside of some of the very top players and teams) than I had previously thought, especially in the Premier League.
This is an interesting topic and something that would make for more in depth thinking beyond this five minute stream of consciousness writing style.