I think your beliefs are nonsensical.
Kimi had driven exactly two races with other cars on the track in the last 3 years when he came back to F1 this year. Didn't seem to have hurt his racecraft much.
Hulkenberg did not race at all last year, he's done a great job this year.
Damon Hill had driven exactly 2 races the previous year when he got into the Williams in 1993.
Kovalainen also only did testing in 2006. He was fine in 2007. Maybe didn't set F1 on fire, but did beat the super experienced Giancarlo that year.
How many other examples do you need?
You don't have to agree with me.
Kimi is a once in a generation talent and not a valid example. You're really going to sit there and compare a world champion with someone who you, myself, or anyone else for that matter, cannot say definitively what his career will be? That's nonsensical to no end.;)
Damon Hill had the benefit of the best car on the grid by a country mile in 1993. But the other thing is he also finished behind Senna in the standings.
Yes and Kovalainen is on his way out of F1 altogether.
Since we're talking about Williams, do you recall Heinz-Harald Frentzen? Talk to people who saw him in Formula 3000, and they'll tell you he was extremely fast. How did that all pan out for him when you look at his career? Not quite what people envisioned out of his career when they were watching him prior to F1.
Listen, I hope Bottas is better than advertised. Call me a skeptic, I've heard too much praise dumped on guys who turned out to be ok drivers in F1, periodically capable of a really good drive, but nothing like what the hype built them up to be.