Hi,
I'm reacting to the "firewall" thing.
I'm not sure you really understand what a firewall does?!
A firewall acts on the data traffic incoming or outgoing to simplify its job is to prevent incoming unsolicited traffic.
It won't protect you when accessing your banking account.
When browsing, the user is willingly connecting to a server, in doing so rendering a firewall useless if the server is compromised.
Of course a firewall can block known malicious addresses or allow only known IPs but it is restrictive and not that effective.
To go back to the main topic here : Ubuntu Touch
The hotspot is a bit tricky to activate but it works for most of the devices.
Regarding the move to 20.04, the technical limitations are unknown at the moment so the foundation (or anyone) is not able to give a statement on whether a device CAN or CANNOT be ported to 20.04.
The foundation already gave a list of devices on which they are working. This list will most probably see a port to 20.04.
For other devices it will depend on the porter or if someone step in to do the job ; the core team will be able to help but they cannot port each of the tens of devices supported right now.
I hope this clarifies some things.