It is a "big against for a potential new love" because food isn't just fuel, it is part of how human beings (with a very few exceptions) bond and socialise- always has been, always will be.
Avoiding getting into a close relationship with somebody who has very different attitudes to food to you is usually going to make sense - a vegan wouldn't want to date somebody who's absolute favourite meal was a rare steak, somebody who adores sea food but eats no carbs would struggle with a partner who wouldn't touch sea food but ate mainly pasta and bread...
Couples cook for one another, potentially raise families who eat together and are influenced by their parents' attitudes to food.
Cooking separate meals on a daily basis for the rest of your life, or accepting eating a very restricted diet that is neither appropriate to your own health nor to your taste, is not a happy prospect, because food is more than fuel. Eating out is relevant to early dating but down the line is the least of the problems faced by a long term couple who share a kitchen, a shopping budget and a dinner table, I would imagine... I would still see food incompatibility as a deal breaker at some point in the relationship, and a "not right for me, might as well not waste either of our time" signal on the first date.
I did dump somebody for picking all the salami off a pizza once, decades ago... and do get annoyed by house gets with long inconsistent lists of "won't eats" which make it hard to feed them and my family anything remotely palatable for days in a row (catering for single meals is OK) - living with somebody with similar fussy habits would be infuriating and wouldn't work, because we'd be incompatible...