With wind considered, you got it right in some scenarios... but the weight/mass of the drone have nothing to do with a "safe flight" & only some with stable footage (if the drone movements becomes larger than what the gimbal can adjust for).
The drones you have talked about have a max speed in
Sport: Mini 3P=16m/s, Mini 4P=16m/s, Mavic 2P=20m/s
Normal: Mini 3P=10m/s, Mini 4P=12m/s, Mavic 2P=8m/s (some uncertainty for M2P as DJI doesn't state it, but this is what I recall)
As speed is the only thing that can counter the wind speed you see that it's a bit mixed here... if you still have a connection & can change to Sport the M2P is the clear winner with it's 20m/s. But if you've lost the connection & have to rely on a RTH failsafe... the M2P is the loser, this as the RTH uses the Normal mode speed, which for a M2P is only 8m/s. Furthermore, both the Mini 3P & 4P can utilize the full tilt angle of the Sport mode to maintain the max Normal mode speed if the headwind is too strong which effectively let the 2 lighter drones utilize Sport mode automatically.
So that's about ensuring a "Safe flight".
The lighter Mini drones are more prone to more erratic movements in gusty winds though... this as they are lighter, meaning have less inertia. This only becomes a problem for the footage if the gimbal can't keep up... & so far we have seen very little about this in the forum... so probably no major problem. In this regard... the M2P, with it's larger weight, will safe guard this further.
But with all this said... the M2P is a good drone, I'm sure it will make you satisfied