No.
The tractor is only carrying the blower during transport anyway. When in use the blower is self-supporting.
What about when you need to raise the blower to assist maneuvering? That's precisely when the front tires need added traction if possible, especially in snowy conditions. Shut down completely the blower first? Nah.
You never raise the blower during operation? I do. All the time, but mines a front mount. The principal remains the same. If you're within the safe operating range of the PTO shaft to tractor and implement angle there's no problem raising and lowering while engaged and working.
And it's mostly being raised to maneuver a bit before lowering to the ground to keep working the snow. Hell, I even hit super-high snow banks with it raised fully under full power to top them before carrying on on the ground.
And I'll give another example of needing front weight to help maneuver while the rear PTO is working:
My 60" rotary mower is regularly getting raised while spinning. And a post hole auger. Same.
My first thought after reading OP's post was there's "suitcase" weights that hang on the tractor's front frame that would stay out of the way, leaving the loader available for snow work instead of carrying gravel or whatever for ballast. Good luck if the gravel piles are frozen.