People in EU buy Russian natural gas and see no problem with it. What are you talking about.
Source: https://energyandcleanair.org/june-2025-monthly-analysis-of-...
It's not (only) a matter of cost, but availability. People need fuel to heat their houses. In order to fully replace Russian gas, other facilities (like LNG container terminals) need to be built. That has been done and is being done, but is complex and not instant.
Should it have been done before February 2022? Yeah, probably.
When the war hopefully will be over, sanction lifted and there will be no problem with trading with Russia anyway.