Making opponents choose between wasting resources, limiting their offensive, or attacking elsewhere.
For now, however, theyre a great way to try out the new set on a budget
Vintage kept its restricted list, because some people wanted to play with powerful cards (and also because Type 1.5, aka legacy had started to take root, which, at the time, was just vintage with the restricted list renamed "banned list"), but in standard, you already couldn't play with all your cards, so there really wasn't any good reason to keep a restricted list
An ideal jumping-off point for those who didn't buy in from the beginning
They can be solved fairly easily, and, unless combined with the other half of their combos (proliferation of counters, Mycosynth Lattice, Wheel of Fortune), dont have a huge impact on the game for more than a couple of turns