There's no evidence for that at all.
Listing the threads (e.g. via New Posts) has always been fast for me. Actually opening a thread is slow, that's why I try to save on time by only opening threads which seems to be about something interesting. Now we're _forced_ to open them in order to know.
Even though some people read ITT only on a tablet, why do you think that should be the only option? For me that would be an impossible thing to do, as I actually try to read every new posting in the threads I'm interested in. There's no way I could possibly do that on the tablet, by far. I use the desktop, and that one _does_ have a mouse connected.