Hakkinen's damage in terms of his racing ability is unknown and being close to death doesn't mean he wasn't fully recovered as a racing driver - see Massa who insists he was fine afterwards, as does Rob Smedley. But Schumacher's damage from his 2009 accident is known: https://www.thinkspain.com/news-spain/2 ... irms-medic
It was a permanent injury. That and being a month short of 44 by the time he retired.
But I agree that Formula Cheese Tyres would have prevented us from seeing the best of prime anybody. I remember thinking at the time that the Sennas and Montoyas would have been completely under the radar under these tyre rules.
On Hamilton, we never got to see the complete article until he was from 32 onwards from 2017. He was 26 in 2011 and Schumacher was his prime self at that age in 1995 and from about the ages of 25-35. That's a longer operating window than Hamilton and if I was a team principle who had to pick one to drive for me for 10 years from 25-35, Schumacher is the obvious pick, let alone his team building capabilities. His worst season was 2003 and that was still at least as good as Hamilton's 2011,2013 and 2016.
On Rubens, I'm glad to see other people recognising that he was every bit the same tier as Button, Alonso, Kimi and Montoya. The fact he was beaten by Schumacher made them both look slower than they really were, like Kubica/Heidfeld and Bottas/Hamilton.
And about Schumacher's other "unfair advantages":
1) Unlimited testing - EVERYONE had unlimited testing, some teams diverted their resources elsewhere under the same rules and there was nothing stopping McLaren from hiring/buying a local test track and undertaking testing programmes. The reason they didn't need to is primarily because of 2...
2) Bespoke tyres - while it was clever politicking from Ferrari to get Bridgestone to give them bespoke tyres, it was a strategy that backfired and you could see it backfiring from as early as 2002 when Montoya kept getting pole, and it got worse as the years went on. There was a mass exodus of teams to Michelin and the combined testing mileage of Michelin was much larger than that of Bridgestone. Ferrari and Schumacher did NOT have a testing advantage over the competition, they had a disadvantage. Aero testing was mainly done in wind tunnels, track testing for aero was mainly for installation and refinements. Testing was most useful for tyres.
By 2006 after Bridgestone were crushed in 2005, Jean Todt was campaigning for teams to rejoin Bridgestone - by which time Alonso too had bespoke Michelin tyres - much more highly tested Michelin tyres.