payn
Glory to Marik
Yeap, if you want the numbers treadmill tradition growth and magic item golden showers, Paizo ate that lunch with PF2. D&D went in a new direction.In 5 if I throw a band of dozen CR 2 monsters against a 6th level party I don't expect it to be deadly but it would likely be a challenge. Kick up the numbers by another half dozen and I'd likely be looking at a TPK. If it's a 10th level party I'd likely start using mob rules if I didn't for the 6th level party but once again if I throw a small army of CR 2 enemies at them it's going to be a challenge.
In 3 or 4 I would never bother because they would only hit on a 20 which meant that we just had the escalator or ever increasing numbers that gave the illusion of growth. In 5 if we use a monster that gets advantage like berserkers and don't hand out AC boosting items like candy and those CR 2 monsters are going to hit even higher level PCs in the party about half the time. In 5th I'm more likely use the CR 2 monsters as cannon fodder for the big threat but they are still more than just a speed bump.