I consider myself a marxist, but do not support either country. Lenin and Mao did some good things and I'll credit them where I believe it's due, but what China and the USSR eventually became is not something I can support. Based off what I've seen on this site it seems you're not allowed to be a marxist unless you also support these states. Is there some lesser known tendency of marxism that doesn't require support for these states?
What exactly is critical support?
Like you said "Lenin and Mao did some good things and I’ll credit them where I believe it’s due, but what China and the USSR eventually became is not something I can support."
Support the good, be critical of the bad.