Refuelling was banned because 1) it was dangerous, and 2) Ferrari at the time was dominating with Schumacher, they had perfected a technique based on multiple refuelling stops during the race that most other teams couldn’t employ (they had different tire manufacturers that couldn’t match Bridgestone’s performance on short stints). So F1 banned refuelling and moved to a single tire manufacturer for everyone (as well as banning in-season tests, which only Ferrari and a couple of other teams could afford).

Bernie Ecclestone and Max Mosley, for all their shortcomings, were absolutely ruthless when it came to nerfing teams to guarantee competition. After they left the scene we’ve had almost a decade of complete dominance by one team.