[mytailorisrich]

Yes, towards London it starts to really fill up after Maidenhead when arriving in Burnham and, especially, Slough (as was the case with GWR trains before the Elisabeth Line, really).

Before that it's only people who commute locally between Reading-Maidenhead-Slough where driving is a competitive alternative so it's not too busy.

The Elizabeth Line does improve commute within London but in locations like Reading I think people would have preferred more and cheaper fast trains to Paddington as the Elizabeth Line makes no difference for commutes into London or even more local commutes.