Based on how these people act, yeah, I think a number of them (not all) DO find most ships to be interchangeable except for gender/race/other privilege and power dynamics.

I remember seeing one person very insistently writing (and at least a few people uncritically reblogging) "if you ship this white man/white man ship, you HAVE to include this WOC (an ex/good friend) or else you're racist" as if the dynamics of a same sex OTP are the same as of a mixed-gender OT3.