Poland is the only European landpower with significant means and the brains to go all-in.
I'd say it is possible, but it will be difficult to realise. It's not so much a question of ability but one of will. In most European countries, there is already a strong minority against aiding Ukraine. If that aid is to become one of putting boots on the ground, minorities could easily become majorities. I'd expect a lot of help from Poland, Britain, Sweden, Finland and possibly France, and less so from Italy and Turkey. Germany is a question mark, it all hinges on the outcome of the upcoming elections.
Poland is not a European land power by any means.
Google AI says:
The Polish Armed Forces have over 292,000 active duty personnel:
- Land Forces: 100,200 active duty personnel, plus over 40,000 in reserve
- Air Force: 46,500 personnel and more than 261 aircraft
- Navy: 17,000 personnel and 46 ships
- Special Forces: 4,000 personnel
- Territorial Defence Force: 55,000 personnel
So, out of this 100,200 active duty personnel, just about 40,000 are combat-ready troops and these 4000 special forces soldiers count as well.
Territorial Defence forces are weekend soldiers who have repeatedly failed their certification. They cannot do most combat tasks and don't have any heavy weapons.
Even amongst land forces, there are many soldiers whom other soldiers refer to as "socialists". Let's say, somebody earns an equivalent of €1100 before tax as a cashier at a supermarket. He/she joins the army just because they can earn an equivalent of €1500 before tax as a private. They have free food and accommodation on top of that, but they have no motivation apart from the money.
Also, Poland has no reserve forces.
90% of 155mm SPHs, 50% of tanks and over 50% of IFVs and APCs have already been donated to Ukraine. Unlike most European armies, the Polish Army did not donate their reserve equipment but the active one, no matter how new/old it was.
Poland produces no ammunition but assembles 40,000 155mm shells a year that are made of components imported from Czechia.
That's what RuZZians normally use in two days.
In contrast, Poland had over 300,000 conscripts at the beginning of the 90s plus 1 million reservists.
The Baltic countries introduced a draft, but Polish political parties are not ready for that out of fear of losing elections.
I don't think Poland will be able to build an effective army before 2035.