The regular M2 won't be as powerful as the M1 Max in the entry level Studio. You're talking an M1 with 8 performance cores and 24 GPU cores vs. a M2 with 4 faster cores and 10 GPU cores. For the sort of multi-threaded, GPU-heavy tasks that the Max is aimed out, the M1 Max having twice the number of cores will likely trump the individual M2 cores being a bit faster.I can imagine they won't upgrade the Mac Mini to M2 until they also upgrade the Mac Studio to prevent a powerful Mini cannibalizing the cheapest Studio.
The M1/M1 Pro/M1 Max distinctions are also about RAM capacity, number of ports supported and number of displays supported. The regular M2 will likely have similar restrictions to the M1 in that respect (since its #1 priority will be MacBook Air and iPad where they're not a problem).
...what might be a bit more problematic is a M2 Mini co-existing with a M1 Pro Mini/Studio (which is the rung currently missing from the Mini ladder). Similar arguments apply to M2 vs M1 Max, but it's a closer-run thing, especially on GPU performance where 10 next-gen GPU cores might give 16 old-gen cores a run for their money, and I don't think anybody knows how many TB ports the Pro can actually support.
If you look at the M1 release cycle, we've had the regular M1 in Nov 2020, the M1 Pro and Max in Oct 2021 and the M1 Ultra in March 2022. So it would be somewhat surprising for the M2, M2 Pro/Max and M2 Ultra (if it follows the same pattern) to all appear simultaneously. Also, the regular M1 machines are the oldest, and first in line for an upgrade.
I'd say that we might (nothing is certain) get a M2 Mini before too long - maybe at the same time as the M2 Air (they don't want to keep making M1s any longer than they need) but I'd be very surprised if M2 Pro/Max turn up until Apple are ready to upgrade the 14/16" MBPs.
The M1 Pro Mini might be a no-show because in a few months time it could be up against a M2 Mini.
On the other hand, it wouldn't be the first time that there had been nothing between a <~$1000 Mini and a $3000+ headless desktop. Even the 2018 i7 Mini was knobbled with a feeble GPU. The M1 Max version of the Studio at $2000 is already a "rung" that never existed before. Even the Trashcan started at $3000, the Classic Mac Pro at $2500 (with feeble RAM and storage specs).
It's an awful naming system. Apart from using "pro" to mean something different than it does with Mac models and using "max" when they knew they had something max-er in the pipeline (did they learn nothing from OS X Lion?) we have the architecture generation up-front (so M2 is slower than M1 Pro, let alone if we end up with M2 Pro vs M1 Max....) - then there's "M1" ambiguously referring to both a specific chip model and the whole M1/Pro/Max/Ultra/Quad range.M series, Pro, Max, Ultra... it's kinda confusing naming system. Ultra has more than Max, doesn't max mean maximum? Have to wonder what they will name the chip configuration in the Mac Pro.
Seriously folks - no point reacting to rumours about M2 launches by saying "that would be confusing" - the confusion is already a done deal.