(Wow, I didn't think my posting would hit so many nerves!)
You are absolutely right, as I conceded to Shortround6 in regard to the Mid-Atlantic: In a scenario populated by low-performance planes (low performance in everything except for range), the Fulmar could do well. The one-eyed man ...
Welcome to the forum; yes, you hit a number of nerves.
While top speed numbers are interesting, they are only representative of a certain condition e.g. clean (i.e. no external stores), ideal altitude, etc. And we will note that piston engines are often only good for max power for a very short period e.g. 5 minute limit and they were extremely hard on fuel when operating at max power - not quite as bad as modern jet on afterburners but way more than cruise (planes are using excess fuel for cooling). And that planes, especially torpedo bombers, had to fly low and slow to "belly flop" their ordinance in without damaging it.
It is often more illustrative to look at cruise speeds. He.111 - 190 mph; SM.79 - 161 mph; B5N1 - 161 mph; Bf.109E - 233 mph (Aside, while Bf.109E maxes out at 348 mph at altitude, it only makes 290 mph at sea level. As with the Soviets, if you can drag the German fighters down to the deck, their advantage is negated.)
And ideally our interceptor has an altitude advantage - so will be exceeding its max level speed.
So, the Fulmar often has >100mph speed advantage over the Axis bombers as they approach the RN convoys as it attacks.
Had I been in FAA, of course I would have preferred a high performance single seat fighter - I'll take a Hawker Sea Fury thank you kindly. But given how technology changed between specification being written and plane coming into service, the Fulmar wasn't all that bad. I think Fairey could have done a much better job, but FAA needed it now, not next year. The FAA requirements didn't help - RN needed planes for their next generation carriers (Ark Royal/Illustrious class) - being 10+ knots faster than Argus - when they relaxed the landing restrictions, the FAA got better planes.