So pretty much he'd never be able to put together a modern championship campaign. So pretty much Mansell lucked into his only championship by being in an uber car with a lower tier teammate? So pretty much if he was teamed up with Prost in the 92 Williams it would've just been Prost's championship?
Nobody at the time thought Nig was an undeserving champion (unlike, say, Hill or Villeneuve) because hed built a reputation as a gifted driver well before in the 8 years prior.
In the 80s, he earned respect for having the measure of his fast yet classless cunt of a teammate who used every dirty trick in the book to try and destabilize him
(Incidentally Piquet was a top tier driver good enough to win 3 WDC titles, so its not like Nig hasnt proved himself against very formidable teammate )
He would have been the WDC in 86 if his tyre hadnt blown up and he probably would have won in 87 if he hadnt had the back injury late in the season.
He was the only driver who regularly challenged Senna's times in qualifying and one of the few drivers who would not back down from a fight with Ayrton.
He had awesome wet weather prowess (getting second place at Silverstone in 88 in a dog of car) and probably has more spectacular, balls to the wall overtaking maneuvers than any other driver in his era.
Therefore, by the early 90s, Nig was considered one of the top drivers on the grid and after years of misfortune and bad luck, nobody begrudged him a WDC that was practically gifted to him. Senna himself that season said Nig had elite skill and was a worthy WDC winner.
Having said all that, his attitude towards a car (just get in and drive the hell out of it) wouldnt work in today's era, because of all the work drivers have to put in off the track. Mansell would get in a car, rings its neck, then go play a round of golf over a race weekend. You could do that in his era because the cars were less complex, but today? We see whats happened with great drivers (Raikkonen) who dont put enough work in back at the factory.