Before answering your question, I guess I’d have to ask my own:

Since poop particles will coat the inside of the toilet lid, do you wipe the lid clean immediately after the flush (to prevent bacteria from spreading all over the seat) or do you wait until you have to use the toilet again, and wipe the seat clean so your back isn’t in close proximity to the inside of a toilet lid that’s covered in poop spray?

I hear many laypeople talk about the aerosol effect, but never hear any guidance from the health authorities about it other than, “You should wash your hands after using the toilet.”

Also, the bum gun style of bidet is just like a miniature shower head. Whatever residue there may be would get washed away each use. It’s pretty trivial to wipe down your own hand-held bidet before/after each use, and the toilet seat style bidets nearly always come with a self-cleaning feature.

If you’re that stressed out over the idea, do what works best for you. Germaphobia is real. As for cleanliness, the Japanese are some of the most fastidiously clean people, and they generally have no problems using public bidets.

It would seem to me that if bidets were as unhygienic as some people find them to be, that countries where they are most prevalent wouldn’t have a prolonged history of using them, and wouldn’t be horrified by how other cultures have no problem scraping poop with their hands from between their butt cheeks.