Several billion people understand and make good use of the standard HTML scroll bars.
For any change, on the first day, only the programmer understands the new scroll bars.
For an Internet user who each month or so goes to dozens, maybe hundreds, of Web sites, all the new scroll bars are something new to learn likely particular to that site. So, for that user, a significant part of the Internet becomes dozens or even hundreds of times harder to use.
Same for standard HTML push buttons, links, check boxes, radio buttons, multi-line text boxes, single line text boxes (and the ones for passwords), etc.
Changes make the site obscure and significantly more work to use.
Web site owners: When I see a Web page with an obscure user interface, commonly I just do a single left click on the X in the upper right corner of the Web browser instance displaying that page.
Beyond an obscure user interface, often I can conclude that the Web site does not want me to see the content on their Web pages because they cover up the content with pop-up windows or expand and contract some header material at the top of the page, material that wastes limited vertical space on my screen.
Another problem is Web pages that follow my mouse pointer and respond to its position without my giving a click. Big interruption in using the site. Nearly always I'm just trying to bring the window to the top of the Z-order so, instead, have to swat like a dozen flying insects the various responses to the mouse click -- again, I do want to see the page and just want to bring it to the top of the Z-order.
Then there is Web site code making the window larger -- again it's like swatting flying insects. No, no, 1000 times no, with rare exceptions, I do NOT want any one page to hog my screen area. The reason is fundamental: In visiting the page, I'm trying to get something DONE, and that requires seeing at least two windows, maybe a few more than two. When one program takes up all or too much of the screen area, I can't see the other windows I need and, thus, can't get the work done.
There is an old remark that goes something like "Just because you could doesn't mean you should."-
> Same for standard HTML push buttons, links, check boxes
Interesting that you mention checkboxes. For a long time native checkboxes on Linux (distro?) would come up impossibly tiny if you had a decent-sized screen. They were hard to hit accurately with a mouse, and impossible with a trackpad. That seems to have been cured now, but I don't know when it was fixed.
For any change, on the first day, only the programmer understands the new scroll bars.
For an Internet user who each month or so goes to dozens, maybe hundreds, of Web sites, all the new scroll bars are something new to learn likely particular to that site. So, for that user, a significant part of the Internet becomes dozens or even hundreds of times harder to use.
Same for standard HTML push buttons, links, check boxes, radio buttons, multi-line text boxes, single line text boxes (and the ones for passwords), etc.
Changes make the site obscure and significantly more work to use.
Web site owners: When I see a Web page with an obscure user interface, commonly I just do a single left click on the X in the upper right corner of the Web browser instance displaying that page.
Beyond an obscure user interface, often I can conclude that the Web site does not want me to see the content on their Web pages because they cover up the content with pop-up windows or expand and contract some header material at the top of the page, material that wastes limited vertical space on my screen.
Another problem is Web pages that follow my mouse pointer and respond to its position without my giving a click. Big interruption in using the site. Nearly always I'm just trying to bring the window to the top of the Z-order so, instead, have to swat like a dozen flying insects the various responses to the mouse click -- again, I do want to see the page and just want to bring it to the top of the Z-order.
Then there is Web site code making the window larger -- again it's like swatting flying insects. No, no, 1000 times no, with rare exceptions, I do NOT want any one page to hog my screen area. The reason is fundamental: In visiting the page, I'm trying to get something DONE, and that requires seeing at least two windows, maybe a few more than two. When one program takes up all or too much of the screen area, I can't see the other windows I need and, thus, can't get the work done.
There is an old remark that goes something like "Just because you could doesn't mean you should."-