The atmosphere in the away end is mostly linked to the performance/outcome on the pitch.
I think over a 5-10 year period or even going back 30 years I doubt there has been a set of away fans that have been in and around the Premier League that have endured a more frustrating/tedious or miserable experience as us Evertonians.
It's the same every season with us. We never beat the Sky 6 away (the COVID season was blatantly down to there being no fans so we managed to beat Spurs, Liverpool and Arsenal in the same season).
We very rarely pull off dramatic comeback wins.
Those smaller clubs who have been up and down will have a miserable time once in the PL but in their promotion seasons will have been having a great time winning most weeks. And nearly all of them will have beaten the Sky 6 away more recently than us (the big games).
Look at the atmosphere at Leicester away a few seasons ago when we won. That away end was bouncing and the credit system was exactly the same as it is today. It's nothing to do with the credit system.