Republicans are pretty unlikely to support such leftist notions as democratizing the means of production, whereas your average FAANG employee just might.
the "American mainstream left" has been:
Silent on their idol Biden bombing a middle east country.
Hawkish on having a confrontation with China. Even a military one.
Calling for any people with real or perceived criticism of them to be cancelled.
Organized the BLM protests which caused 100X more economic damages than the crazies in the Capitol.
They are in bed with the mainstream media, the technology oligopolies and the entertainment industry where their worldview is relentlessly pushed and any dissenting opinion is squashed. They still call themselves victims.(Victims who act like executioners)
They are silent on their hero Biden expanding jail facilities for latino children. Total silence and the few mentions are just euphemism= "expanding facilities"
AOC -> Silent
Bernie -> Silent
Krugman -> Silent
Reich -> Silent
Faang Employees -> Silent
Ilham Omar -> To her credit, she spoke out.
If by "actual leftist" you mean people like Rania Khalek, I would agree, but unfortunately people like her are a tiny minority and constantly belittled, ignored or called tankies or something along those lines.
The mainstream left is dominated by the tech companies, by the mainstream press, by the universities and by the entertainment industry, all coastal highly privileged, 2% of income elites. Those are the people dominating the discourse and as Chomsky said they are "Manufacturing Consent". That includes a big portion of the "commentariat" here too.
But also you're just wrong.
AOC on relief checks (Feb 7th) https://twitter.com/AOC/status/1358244213918494722
AOC on abolish ICE (Feb 24th) 1364349732760518657
Bernie forcing a minimum wage vote (7 hours ago!) https://twitter.com/SenSanders/status/1366545093876924416
30 seconds of searching on the leftist's favorite communication platform. I think the problem might be more that you're not in the right echo chamber... or something.
Bernie Sanders: https://twitter.com/SenSanders/status/1365361968513744897
Ilhan Omar: https://twitter.com/IlhanMN/status/1365150215708299271?s=20
This took 10 seconds to find. You can make an argument that they could be louder (and I'd definitely agree with you on that), but you can't in good faith make an argument that they're "silent". As for Krugman and Reich, I don't see how they're any relevant.
AOC is so vocal about abolishing ICE that I don't feel the need to even back that up.