The joking "close to left wing critique" description is more about this first part of Trumps quote, while the later half is about Powell sucking for not supporting him

Wonderful to see Colin Powell, who made big mistakes on Iraq and the so called weapons of mass destruction, be treated in death so beautifully by the Fake News Media.

Which yeah, its embarassing that the "left wing" politicians couldnt even do and call out this. Its legit to point out the absurdity and shittiness that is this "reminder" of the WMD and Iraq stuff not coming from the Bernie's and "squads" of the US but from Trump

"one war criminal attacking another war criminal" is what people would be happy for if Bernie pointed these things out. In this case, since Trump is obviously an extremely self serving and evil human being its just legit to shake your head that the bare minimum of mentioning or alluding Powells crimes has come from him