For me, who just switched from Windows to Mac, this behavior is also a nightmare.
I can hardly believe that this is accepted by Mac users. You have to use two hands (!) just to scroll through the filmstrip, intuitive operation is something else. I’m getting the impression more and more that the Apple community hasn’t noticed how Windows has overtaken MacOs in terms of usability and design. It seems that people here have become accustomed to cumbersome operation. This doesn’t just apply to DxO Photolab.
But at least other programs offer the possibility to adjust this behavior, but DxO has not addressed this issue for years, although it has been requested again and again.