Cosmology is not even close to theories that approach consensus among physicists. Back in the day the Big Bang theory once did, but since the advent of string theory(s) that's been lost. Simulation theory, E8 holographic theory, Pilot Wave, on and on. Dark Matter and Dark Energy comprise >96% of matter, or don't even exist. Even when we had a cosmology that did have consensus that lasted for centuries, it was proved wrong by Einstein. Newton's orbital maths are still used in rocket science, because they're close enough to get spacecraft safely to orbit and back, and they're a lot simpler than Einstein. The cosmology developed from them is not close to reality however, and no one seriously claims the aether exists.

Pretty much a crap shoot.

I have seen pictures of viruses, pics of SARS2 in fact, busting out of cells. However the anti-germ theory folks claim they're just exosomes. As a biologist I am pretty confident in the germ theory of disease, and reckon viruses are real too. That is not a claim there's a pandemic or that Covid is more dangerous than the flu. The jabs are definitely more dangerous than the flu, however. There's a lot of evidence of pathogens.

Proof, though, is not a scientific concept. Nothing can be proven, and Newton's theory is a good example of that. I can't even prove I exist. I'm ok with that. I'll go with a preponderance of evidence.