It depends, drivers of today require less skill than drivers of Fangio or even Senna's era. And while you occasionally hard constructor's cars which dominated back then, it generally wasn't for a lengthy period of time.
Hence, Senna often had to win races with a car that was significantly worse than the top cars of some seasons. Then again, back then, that was far more possible as driver skill was far more important with cars being on the ragged edge of performance and grip.
Now with all the rules and regulations trying to make things "safer," you lose that dangerous edge that depended on a driver being truly great.
I still love watching old races where the cars are sliding all over the track. Modern day F1 racing is rather boring in comparison.
I'd love to see how Vettel, Hamilton, or Alonso would handle a car where the back end regularly breaks loose due to loss of grip from trying to be the fastest person around a lap. And then do that for an entire season with other drivers trying to cope with the same situations. Just watch some of Senna's races. His control is so beautiful it brings tears to my eyes. Noone of his era or this one came close to being able to keep his car on the very edge of performance without crashing as he was.
Probably why, it's almost universal among F1 drivers past and present to proclaim Senna as the best F1 driver ever despite his shortened career.
Regards,
SB