The last 30 years Porto has 17 or 18 league titles (including this years). Benfica has 8.Benfica might historically be a bigger club, but that's like saying we're the big team in England. Or Sunderland. History is history. Now Benfica has had a minor change of fortunes the last 5 years, but it doesn't change the fact that Porto is the top dog, and has been for quite a while.
And that's before we talk European football.
Neymar and Mbappe, Fabregas are irrelevant. I'm not sure you are getting the point. Single star players for a few clubs does not make it a good league. You will always have some few exceptional players in these leagues, but the overall quality is absolute shite. And that's where the championship takes the lead in terms of quality. The championship might not have Neymar or some CL players here and there, but the defending, tempo, figth and overall play is far more competitive than anything you see in Holland or Portugal. By some distance. By having a shite league where the few top teams end up in the CL you will always have some good players in these teams.
The Norwegians heading to the championship are generally accepted to be much better players than those heading to France. Stefan Johansen is generally accepted to be one of our better CMs. Those heading to France, IF successful end up in the championship by large. Or the PL. One of our better fullbacks Meling just went to Nimes. Which is the equivalent of Swansea in a worse league.
By using your own metric if a league is good or not, i.e. if it has big teams and big names. Stefan Johansen went to Celtic. Played there for years. Then ended up in the championship. Celtic is a huge club. It doesn't change the fact that the championship is better quality than the SPL.