I hope this works out. I did sort by forum name, but the thread titles turned that into a scrolling nightmare to find forums. I realize I can subscribe but I dont want to subscribe to other forums than what I have. I just scroll the list and dip into what looks interesting at the time.
TBH, while I like the colors and its clear the layout is trying to be way more modern, Im not in love with the mobile view. The current DU is so much more responsive and respectful of real estate on a phone. On some DU 4 pages, the forum chrome takes up about 3/5 of the screen. The tabs are enormous, for example. My phone is an iPhone 13 Pro Max and I always use the Safari browser. For comparison, the layout on an iPad is much, much better and less busy. Much more attractive and inviting.
I hope this helps. I suspect Im not in a minority of people who consume DU on a phone, especially among working people who grab a quick look-see on a lunch break. I hope the mobile experience doesnt go from good and simple to demonstrably worse.