What you actually give up by not installing an app
Running in a browser is the whole point of this site, so it would be easy to pretend there is no trade-off. There is one. It is just smaller and in different places than most people expect.
What is genuinely better in a browser
Nothing to download, nothing to update, and no install prompt standing between arriving and seeing someone. You are also not handing a permanent app your contacts, your notification permissions, or a background process.
It is the same page everywhere. There is no separate build to hunt for depending on which phone you own, and no situation where the version you can get is behind the version someone else has.
What is genuinely worse
Push notifications while the page is closed are weaker in a browser than in an installed app. If you close the tab, you are gone until you come back.
Backgrounding is stricter too. Mobile browsers aggressively suspend tabs, so leaving the page to answer a message can end a call in a way an installed app would have survived.
Things people worry about that do not actually differ
Video quality is not the trade-off people assume. Browsers have had the same real-time media capability as apps for years, and the limiting factor is your connection, not the container.
Camera and microphone access is also not weaker — a browser asks you for the same permissions, just per-site instead of once at install.