For example Winston Churchill lamented deeply the loss of India and considered Gandhi an annoyance.

Another reason was that the American system of rule based relations instituted after second world war meant former colonial masters could still economically utilize the raw inputs from their colonies without risk of losing the colony to another colonial power and hence being cut off from those markets and resources.

Before second world war any territories unable to defend themselves from european powers were more or leas up for grabs - hence you were afraid that giving your colony independence, another colonial power would have simply annexed them, thus you would lose the resources and the market.

The US rule based order was overall good for the world, regardless of so many documented events of behaving as dicks within it.

Racist thinking was prevalent and helped justify colonialism and humanism existing at the same time.

But you’re right, if Russia loses, everyone will win, even Russians.