To be honest, I've never really thought about viewing all tips on the same page, although that is very convenient. A fine feature that should probably be adopted by Duolingo as well.
The convenient one-page format ~~solves~~ mitigates a different issue I've been having lately though. Duolingo doesn't consistently publish (existing!) tips to all Duolingo frontends/apps. Well-supported languages get the best tip-content support, but languages that aren't as supported sometimes don't have tip present even if the tip content exists.
For example:
- Duolingo Web always has tips if tip content exists. This acts like a source of truth, as far as I'm aware.
- Spanish is a language which has tip content both on Web and iOS. I believe this is because Spanish is popular and well-supported.
- Greek is a language where tip content is not accessible via the iOS app, but is present on the web site. I believe this is because incorporating the presentation of tips is probably some hardcoded markup thing (React?) and nobody has gotten around to doing it yet. Also, there's a possibility that the underlying documents need different rendering treatment or style enforcement, and have been omitted from the mobile app on purpose. Still, this is a thorn in my side.
So for me, a one-page-tips fills a gap in the Duolingo UX (which should probably probably be fixed on Duolingo's end since this simply seems to be a prioritization/maintenance/time/effort problem).
As a user, I'd like an easy way to refer to the tips before each lesson without pulling up the actual Duolingo web app - otherwise, why don't I just do my actual lessons on the web app as well? Usually I'm doing lessons on my phone, not my computer, because the phone is not only more convenient (small) but it's easier to change keyboards and type in non-latin alphabets.