Don't you feel dirty as a developer ever doing _any_ join because you know at scale someone will have to undo this join and break it apart between two services?

Don't you feel dirty as a developer ever doing _any_ join because you know at scale someone will have to undo this join and break it apart between two services? OR, should we accept that some projects will never get to that scale and just go ahead and join! It's like we are plumbers and sometimes we work on small houses and sometimes huge skyscrapers but every small house thinks they are going to sky scrape some day soon.