they are just listed in spells so far so what makes you think they wont be in the PHB? and as the OP said
if they were listed under class feature instead of spells it would dispel this issue 100%
buut are listed in the spells section under cantrips as warlock cantrips.
I don't think they are general, just warlock cantrips, and it is easy enough to see warlock class as able to take warlock cantrips.
since bard has spells from only part of a spell list and has some from a different spell list, you are telling me it is that hard to imagine "warlock cantrips" count as cantrips for warlocks?
again this is confuseing... if a spell is a wizard spell a wizard can learn it right?