I had never thought about it but I think you are right.
I used to like “Smallville” despite it’s obvious PC moments but Season 7 seemed to be the end. It lasted one or two more seasons but I had quit watching by then.
Like M*A*S*H lasted three times as long as The Korean War.
You’re lucky. I stuck it out and the ninth season had the requisite illegal alien episode (the guy hiring them was murdering them and Clark x-rayed a field full of skeletons) and the tenth was anti-military, anti-Christian, with an evil conservative talk show host version of New God character Glorious Godfrey. That tenth season soured me on the whole series and I never want to see it again.