Going through a number of D&D books that feature the Solar I noted that it is amongst the most powerful monsters in the book, frequently only matched in level and power by the likes of the Tarrasque. When you compare them to the other top level Outsiders it won't be much of a contest if pitted against each other, like how for example a 3.5e Pit Fiend is no match for a Solar. This seems to be consistent through a number of editions and endures to this very day.
I am wondering if there is any reason for the Solar to be one of the most badass beings in the books? Is this based on historical equivalents of Monster Manuals (grimoires that detail how to summon demons, some of whom mentioned to never ever try summoning angels because they'd wreck your face)? Or is there another reason why the Solars are consistently some of the most badass monsters in Dungeons & Dragons?