That's crappy, but have you seen what other remote apps are doing?
Vizio has an ad that takes up around 25% of the screen!
MyQ has a large scrolling ad at the top, and they are actively hostile towards any integration that allows you to control your garage door without using their app (unless you use one of the very few subscription-based integrations they offer, of course).
I recently stopped using my firestick. Even though I only used it for Jellyfin, the ads on the home screen were too much for me.
So I swapped it out for a Raspberry Pi with LibreElec as the OS, and there have been literally no downsides.
Jellyfin for Kodi add-on with Embuary skin shows your entire Jellyfin library on the home screen with continue watching and next up widgets right there when you turn on the TV.
You can set it up entirely through the GUI. Works with either keyboard and mouse or remote.
Uses HDMI-CEC so works with my TVs original remote and even my firestick remote.
If you want to use an app remote, Kore is officially supported and has no ads.
Invidious add-on with the Send to Kodi and libredirect Firefox extensions means I can cast YouTube videos to my TV with no ads.
You can even run an Ethernet cable from your router/Jellyfin server to the Pi. I did this and have not experienced any buffering since.
It even passed the spouse test. My wife says she likes that it's faster and more responsive. Plus she likes the asteroids screensaver.
Roku to me has always seemed like a bogged down, spammy platform. I've always been surprised at how often it gets recommended in cord cutting and self hosting sort of forums.
Maybe it’s because I run Pi-hole; I know it filters out a TON of Roku’s telemetry and other traffic. Might be worth setting up Pi-hole on your network and see if stuff like that goes away?
What Ads? I don't have Ads in the interface nor in the app. Okay the reason could be my openwrt router is set up with Stubby DoT and blocklists from AdguardHome.