I have bidets/washlets installed in my home, and the only problem has been that I now can't go back. Whenever I travel I now have to carry around wet wipes or I don't feel clean. But wet wipes are apparently horrible for the environment.
The problem with wet wipes is mostly that they should never, absolutely never, be flushed. Wet wipes combine with fat in the sewers, and form the basis of an ever growing deposit of solid mass that will inevitably block the sewer (or pipes if you are unlucky and the stuff builds up at an earlier point).
When these deposits grow in size they are known as fatbergs. In London they have had to remove fatbergs the size of double-decker buses, but it's a global problem.
If you use wet wipes, the rule is simple: deposit them in the trash can — just like period products and nappies.
Don't bother believing the 'flushable' wipes lie: all wipes are flushable for sure, but they all contribute to the problem, and none disintegrate before they mix with fat to become a potentially very expensive problem.
> If you're using the ones that are almost cloth-like strength, those really shouldn't be flushed down most sewage systems, even if they're marked as supposedly "flushable"
I have a kind of wet-wipes which are almost cloth-like strength, but dissolve into just a milky jelly liquid if they are in water for a few minutes (I’ve checked products tests first before choosing this specific brand, they even dissolve fast enough to work in train toilets without clogging them up, if you wait a bit before flushing).
NDR Markt has tested different brands available at German stores in 2016, and showed quite extreme differences, while some products had already mostly dissolved after 10 minutes, others were after 3 hours still without any change: https://www.ndr.de/ratgeber/verbraucher/Wie-Feuchttuecher-di...
I can't win.