Just beware: you cannot trust any of WoWProgress stats. The indicated "517 +10s" might have actually mean "500 +25s in Legion and 17 +10s in BfA". My former main char from Legion shows "550 +10s" according to WoWProgress. But when I check its raider.io tooltip in game, I only bothered to time "9 +10s" on this (now) alt across the current season. On the other hand the "517 +10s" on WoWProgress might actually mean "517 +20s or higher" which would give more than twice the number of loot pieces compared to farming +10s.
On +2 there are basically 0 mechanics for a geared 420 group. I haven't played +2 in a while, but I suspect in some dungeons you could pull all trash into bosses, AoE everything down, and it's gonna be fine.
On the opposite end, if you want to time 23s-25s, you may as well consider the entire dungeon equivalent to one 30 min long boss fight with hundreds of abilities, where any misplayed ability will make you deplete the key. To make things worse, you'll have to pull multiple trash packs together, or you might pull some trash (or reaping) into boss fights. In some cases it's beneficial to chain trash, into reaping, into more trash, into next reaping, and play it with boss.
The mechanics in M+ are "still the same" across all key levels, but you can completely ignore and outheal 90% of all mechanics if all you do are some +10-12s for weekly. Even after you get past +20s, well into +23s, you will keep discovering mechanics that you did not have to respect just 2-3 key levels below. And timing a higher key will force you do bigger and more efficient pulls, which will only amplify the difficulty of dealing with multiple mechanics at once.
That is the appeal of pushing M+ for challenge. No matter if you are trying to go from timing +13s to timing +16s, or from timing +21s to timing +24s - you will always be discovering new things, adjusting your pulls, and learning to handle situations that never arised in lower keys.