I mean... It's always Schrödinger's left. When we talk about "the left" it's always a constructed public. Whatever the speaker wants "the left" to encompass is in there. Like you talk to a conservative and "the left" encompasses a party like the Democrats, you talk to a democrat and Depending on the person they might consider themselves leftists or not depending. You talk to a Socialist and "the left" excludes the Democrats. The concept serves a purpose in each case. To create a body of condemnation, to create a nebulous scapegoat, to attempt to build (sometimes false) solidarity out of an incredibly fractured group, to establish an aspirational ingroup or out group... Or to self soothe that one's highly individualized take on politics is not alone.

It's a weakness in the flanks of the way we discuss these things. There's a holier than thou approach to claiming where on the political compass one sits and what is worthy of scorn. The Republican base doesn't seem to have that in the same measure which makes it more dangerous.

I don't think it's resolvable personally. Ditching the concept of claiming "the left" may be key to changing engagement styles to become less armchair criticism of a nebulous ill defined group... And more focused on actually tackling and pushing specific issues with more progressive non-partisan ship.