I’m not convinced that regimes under Stalin or Mao would have been particularly less murderous under some form of capitalism (whether state capitalism, monopolistic capitalist, or other), or that any system birthed by revolutions against Czarist Russia or pre-revolutionary China could/should have been expected to have done much better.
But as for actual consensus: let us not allow the historical record to forget how dumb some policies can be, for example a) forced collectivization and b) killing (or worse) administrators who don’t meet quotas which then prevents people from bringing bad news to leaders if/when they need it. These policies are not to be repeated.
The blame on intentional starving of millions of Ukrainians by Stalin should be blamed on Stalin intentionally extracting a tax that could only have resulted in the starvation of millions.
This is fundamentally different from the millions who starved during drought, in the period immediately after widespread forced collectivization (under Mao).
As for the political brutalities and killings linked directly to civil war and political oppression: This seems rather on par with the histories of each country, and I remain thoroughly unconvinced that communism (excluding forced collectivization in pre-industrial agriculture), per se, is to blame.
This is not an argument for communism. If communism, per se, is a threat to our freedom and economic well-being, then let us base our arguments on fact and good use of reason, not just the most grotesque representation that can be reached for.