Depends on what you consider self-hosted. Web applications I use over LAN include Home Assistant, NextRSS, Syncthing, cockpit-machines (VM host), and media stuff (Jellyfin, Kavita, etc). Without web UI, I also run servers for NFS, SMB, and Joplin sync. Nothing but a Wireguard VPN is public-facing; I generally only use it for SSH and file transfer but can access anything else through it.
I've had NextCloud running for a year or two but honestly don't see much point and will probably uninstall it.
I've been planning to someday also try out Immich (photo sync), Radicale (calendar), ntfy.sh, paperless-ngx, ArchiveBox (web archive), Tube Archivist (YouTube archive), and Frigate NVR.
This seems fairly similar in capability to the Anbernic RG351P, which uses the same RK3326 processor (and by extension the same GPU), similarly has 1GB RAM, similarly has two sticks, and similarly has a conspicuous lack of integrated Wi-Fi. Biggest difference is the screen and body: 351 has a 3.5" 480x320 screen and this is 4" 800x680.
A bunch of Powkiddy devices use this processor too, like the Powkiddy RGB10, RGB20 and V10. Reviews for any of them should tell you how well this'll perform.