In the 19th and most of the 20th century they had us to help, so the empire was held together
There's something to this...
Many Russians obsess over several quotes from Zbiegnew Brzezinski (mostly ripped out of the proper context), the main one of which is that Russia needs Ukraine to act as an Empire. No Ukraine, no Empire. People see in this some proof of America's far reaching plans to dismantle Russian power, starting from the 1980s.
The truth, however, is that if Brzezinski was alive today he would likely be in the camp of Scholz and Biden.
Back to your point... Brzezinski was correct in his evaluation of Ukraine's importance to Russia. As a Pole, he was able to grasp these things in a different way than the rest of the foreign policy establishment in America.
However, I never considered if Poland had a similar role/function....
In some ways, Poland is a bigger prize than Ukraine.
First, the minuses:
1) Yes the population is quite a bit smaller
2) There's a lot less natural resources
3) The territory is also significantly smaller
4) No direct access to southern seas
The pluses:
1) Incredibly strategic position, which allows to project power deep into the Continent
2) 1,100 years of REAL history, not fake history like our little brothers. This should enrich Russia, rather than create endless toxic debates.
3) Member of EU and NATO
4) The largest group among Western Slavs (immediately gives more credibility to Panslavic idea)