I did not know this, but I am apparently one of those few people who use a scrollbar to point to a location where I need to be. Either in source code, manuals, even on some vendors web pages I know the tech specs and the link to the datasheet is 2/3 of the page so I drag or click the scrollbar. In documents, or on webpage I have a mental image of where the scrollbar was when I read it, like page numbers in a book and I use it a lot. And no this is not substituted by scrolling with a mouse wheel or heaven forbid a track-pad. If I know I need to find something at 'M' I do not want to go through all the stacks starting at 'A'. Just saying we have been organizing content for a lot longer than the UX people telling us what we do not need.

Scrollbars are a tool and they should be functional: visible, properly sized and interactive. It helps if a scrollbar looks and functions the same on all our content, because it takes less mental strain to use.

It may be that you don't like scrollbars for your content. The obvious solution is to make your content fit so it does not require scrollbars. If you cannot manage that you will have to live with the fact that scrollbars are there as a functional tool and make sure it is kept functional. In analogy: If I sell furniture you have to self assemble I can choose to design it to not require tools. If it does require tools I should make sure people can actually use those tools to assemble and not try to hide that tools should be used by pretending the thing to put nails in is not a hammer.