Most conditioners are filled with silicones that are not water soluble. But after a while, they break down and make your hair look dirty.

The solution is to remove them, but you can only do that by using strong solvents.

So you use shampoos that contain strong solvents. This damages your hair, so you make sure to use conditioners to repair the damage. Except they don't repair, they fill in the holes with silicones. The silicones are now deeper into your individual hair strands. It looks good, but after a while, they break down. So you use solvents, deeper this time.

This damages your hair. Then you use conditioners. Most conditioners are filled with silicones that are not water soluble. Yet, after a short time...

That doesn't mean you shouldn't cowash, it means you should upgrade to products that do not have silicone (also phosphates). There are various haircare forums that will give you the specific ingredients to look out for.

I'm not saying you shouldn't wash.

The comment we are commenting under is not even saying that but recommending that we pay attention to the ingredients: "Most shampoos are very a agressive for your scalp [...] Using a gentle shampoo without silicones and surfactants"

Here is an interesting web application that allows you to scan products to know their ingredients. It tells you if they contain hard to remove silicones or harsh solvents. https://curlscan.com/

Using it to scan the brands at the stores that are local to me reveals that only a small minority of product do not contain the silicone-solvent circle.

Anecdotal, sure, but I have been teaching this to all the women in my life and they all report back that they are able to go longer without washing their hair with products now that they pay attention to the ingredients. Turns out that for a lot of people, we were going through the motion of adding a coat of product and removing that coat of product daily instead of actually fighting grime and sweat.

I donate my time to help the homeless. I know what people that don't use soap smell like.

The key thing is water. And clean cloths.

Exactly. There is a world between “don’t use soap on your body” and “never shower yourself or change your clothes”. I often wash myself with water two times per day

You are telling me that you are able to detect by smell whether a person is using a conditioner that contains silicones?

It sounds like this person previously had a healthy relationship with hygiene but has somehow convinced themself to just stop cleaning themselves.

Soap and toothpaste are good things. These are miraculous modern inventions. Use them.

These are heterodox views about personal hygiene.