The problem is the stereotype of people who say “It’s what my character would have done.” are just using that as an excuse to dodge blame for having their overly edgy character perform questionable acts such as murderhoboing that ruin the fun for everybody else.

Having said that, understanding what your character would actually do in a given situation based on their current knowledge, background, etc. can make for really good RP situations, but must be done in good faith (unlike above)