I'm not a tankie, but I probably am what everyone in this thread is calling a "tankie", so here's my answer:
Yes, it is extremely bad that Russia invaded Ukraine. The ideal scenario would have been Ukraine quickly repelling the invasion when it happened. But we don't live in magic fantasy world where everyone gets what they deserve. We live in the real world, where Ukraine cannot possibly defeat Russia in a war. The option which saves the most Ukrainian lives is a negotiated peace, with Russia getting much more of what they want than we would like.
All that is achieved by pouring more weapons into Ukraine is prolonging the meatgrinder for years, wiping out an entire generation of Ukrainians and risking a global nuclear war.