HTML backlinks? What and how they do it ?

Lately, I've noticed that a lot of sites are getting links from internal html pages on sites with pretty low quality.
It's very strange because the links in question come under the article, and they take the entire menu from the site to which the link should lead, but when you click on them, they redirect you to another html page with menus from another site under the article.

For example, check this html page:
https://absavenue.com/bepraise13335.html

The links are in the search form, havent seen that done in a while

the last few months in my analyzes are full of links from such type of sites. as a matter of fact I have a list of over 700 domains full of such html articles and links in them

Injected with javascript, usually through hacked domains or "free" shared wp themes and plugins.
Some of them have randomization, to show only once in x times, or to specific IP ranges, or at specific times of day, also some of them recognize admin login cookies so when you are checking the pages links are not visible, etc.
Usually used by trashy low-level scammers for trashy low-level services/products.

They are haсked sites. To google, all web pages are html.