It is clear to me from your opinion that Russia is playing the humanitarian crisis card in what appears to be the most extreme solutions it has, but this is also surprising given the size of the military arsenal it possesses compared to Ukraine. Even on a strategic level, the Russian army has experience in fighting wars, whether on its territory or abroad. Is it really possible that it fails to invade a country that does not have the same experience or tools?
Russian military power is a mirage. Their last major victory was against nazi Germany (thus the bizarre fixation on nazis even to this day) 80 years ago but even that comes with some caveats, such as lend-lease, second front, and the amount of cannon fodder Stalin used up.
Since then they failed in Afghanistan, barely defeated Chechnia (a nation of ~1.5 million) by bombing it into rubble, and incited some smaller conflicts (Moldova, Georgia, Ukraine pre 2022). They haven't been able to create any substantially new weapons and can barely maintain old soviet equipment. Corruption in all levels of Russian government, including military, is legendary.
Here is an interesting analysis on how their claims differ from reality:
https://www.youtube.com/watch?v=eHhgVrKJJoAtl;dr: claimed to have 10+ thousand tanks, may have actually had 3000 potentially usable ones before the start of the war.
In doing some reviews, I think your observation is valid. Russia is winning the wars it is waging on its land due to its icy nature and climate that helps it to withstand in contrast to the invaders who can withstand the harsh winters, and this happened with Hitls and with Napoleon Bonaparte before him.
The rest of the wars fought on other lands were not very successful.
With more support for Ukraine, I think it is capable of making a difference in the war, but we cannot forget that Russia is able to fill the arena with soldiers and weapons without referring to economic weapons.
No, all that is Kremlin crap:
a) The RF is not winning the war, is loosing it. Only in the last few days it has lost 1000 km2 west of Mykolaiv. Kherson is getting close to encirclement. Crimea is close to having the main water supply to the region in Ukrainian control.
b) Winter may not play a role as much as it did in WWII. Things have changed quite a bit. Particularly near Kherson, the temperature in winter is certainly not enough to stop operations by modern standards. Whoever is counting on that is up for a surprise.
c) The RF is not backfilling with "soldiers" is backfilling the estimated 80.000 soldiers killed with a number of forced conscripts with little training and no will to fight. That is not a "soldier" that is a "slave" wielding a weapon.
As for your knowledge of history, it sucks. Napoleon experienced winter far north, pretty much from Moscow and on the way back to France with XIX century equipment - and not even winter equipment as such - and no supply lines. Ukraine is fighting at home with the backing of most developed countries.