Key word: "seemed". Germany always underestimated British strength. Britain always overestimated German strength. The fact remains that, even in the worst of the offensive, the RAF was outattritioning, outflying, and outproducing the Luftwaffe. Britain was suffering, but Germany was suffering even more. Even discounting the fact that the RAF could simply relocate to North Britain, untouchable by Me-109s, if it needed to, Germany had no chance of establishing air supremacy, especially not in time for Sealion.
The website certainly mentions the number of hit airfields. But, even in the worst of the bombing, only 2 airfields were closed for more than a few hours by enemy action. That's terrible.
Also simulations are just computers and never take into account of that 1 man, the one who storms up against all odds and does something so mind blowing no one can believe it.
I can't tell if you're trolling or not. Please offer evidence that Sealion would have worked with river barges, air parity, 10-day unloading times, and overwhelming naval inferiority.