Back then, when playing with 4 minutes on vanilla SoD (no lighter, no HD), some players managed to show a very respectable level that many players of the modern generation couldn't even dream of. Personally, I remember players like Paladin, Stinger, vitalic, Pit, invisible, scorp, Neoandy, Deep Mike, and many, many others. Those people worked wonders at the time. Not to mention that in the chaos league, they played on as little as 2 minutes. Tournaments played in clubs before the appearance of TE were also held with fast clocks. And people still played.
The grass was greener back then.
I agree regarding the chess clocks — it's an incentive to think faster and save time on simple moves so that some remains for the complex ones.
Besides, people choose for themselves what they are more comfortable playing with; there was a vote and it was quite telling.