I think that party descriptions are a display of atleast vaguely where a candidate is on the political spectrum. Its a useful piece of information even if it does increase blind partisan voting, I think the alternative is that elections are instead more based on name recognition which benefits incumbents and candidates with a money advantage.
If you're so uninformed about the elections you are voting in that you don't even know what party the candidates are in, perhaps your ignorant ass should not be voting. Which is why it makes sense that most Dems and Pubs would be against it, they prefer an ignorant voter.
I'm sure there are plenty of people on this website dedicated to election nerdery who can't say they've researched candidates in every single downballot election, so it seems like a ridiculous judgement to say that people who are working all day and not interested in every minute piece of politics are ignorant for not doing that. You don't need to have a mental profile of every single candidate to know generally what you want from politicians.