The dinosaurs were likely wiped out by the asteroid that hit the Yucatan peninsula. I mean, while not all paleontologists agree, there’s something of a consensus about this, and the Chicxulub crater is large enough and dates to the correct time period to explain the extinction of all (non-avian) dinosaurs. Speculating about some alien laser battle in the skies seems ridiculous.

Also, while aliens probably exist somewhere, evidence of alien visitations to Earth from ancient sources is likely all 100% bullshit. The ancients had all kinds of interesting ideas and mythologies surrounding gods, demi-gods, angels and other supernatural beings, and ancient artists and writers depicting weird shit happening in the sky were probably inspired by that kind of stuff rather than actual alien visitations. Consider the bat-shit crazy description of a divine or angelic being in the Biblical book of Ezekiel. The description includes things like spinning crystal wheels, wings, fire, lightning, a crystal dome and multiple “eyes”. It’s easy to read something like a spaceship or whatever into that description, but in reality Ezekiel was probably just high on opium one day, and drew from various imagery inspired by things he was familiar with, like chariot wheels and other ancient equipment.