Safari/MacOs constantly loading page content on scroll?

Question

safari

Good afternoon! Help, please, to understand. There is a site https://malare.pro/ .
In general, the whole site behaves this way, but it is especially noticeable on the product page https://malare.pro/product-category/antikorrozionn...
I check on MacOs in a virtual machine. The client has an iPhone (I do not know the version yet.).

The essence of the problem is that when scrolling, there are constant delays in loading content. At the same time, it doesn’t matter - scroll up or down - as if it constantly updates the elements when they enter the visible part of the screen.

I disabled content blocking in safari - yes, it helped. But I don't understand the logic of how to implement normal loading even when blocking is enabled (not all clients turn it off).

The site is developed on Wordpress. Cached by the WP fastets cache plugin - maybe it has some meaning.