I always assumed this was intentional to push users to the app so telemetry and tracking work more reliably, and to bypass adblockers. The reddit mobile site is

I always assumed this was intentional to push users to the app so telemetry and tracking work more reliably, and to bypass adblockers. The reddit mobile site is a classic example. No new functionality in years, but it's borderline unusable on a phone these days, and the constant nag screens to install the app betray their intentions.