The “streak freeze” announcement dialog can’t be dismissed by hitting the “Enter” key (or any other key, I assume, though I haven’t tried this out systematically). This makes the dialog more disruptive than it should be. In order to get it out of my face and continue playing, I need to switch away from the keyboard (which is what I mostly use) to a mouse or touchscreen.
I have discovered that the dialog can be dismissed by “Esc”. That’s good enough for me, but I would expect people to be surprised that “Enter” doesn’t work.
This all applies to playing on the web on a tablet or laptop. I’m not sure what happens on a phone, either within the app or in a web browser.
I hear you on the friction concern, and I’d go a step further and request that there be an option to disable any mention of streaks in the first place, as I don’t find that motivating. I regularly use Clozemaster throughout the week, sometimes multiples times a day, just not every day. I far prefer Clozemaster to Duolingo, and while I’m not opposed to gamified features in Clozemaster (because they may be helpful to others), I prefer the option to turn off all those features.