My iPad2 can’t do internet anymore, or for instance used as a panel for home assistant webpage or client, but it’s perfectly fine as a homestudio controller and music / midi generator and that is what I still use it for. Battery is still great too. I got it about 13 years ago and I will be using it until it stops working. Looks as good as new too.
I do have a recent iPad too, it’s for all the stuff I cannot do on the old one.
A raspberry pi with pihole running as dhcp server. In the ISP router turn off DHCP, DNS problem solved as pi will advertise its DNS to all connected devices on the network.