dslrdashboard.info

I would like to ask, is there any currently sold device on which the DSLR Server could be installed ?? The vast majority, if not all, of TPlink and other modems or routers are old and no longer available.

You can always use OpenWrt on newer devices and build ddserver for it (https://github.com/hubaiz/DslrDashboardServer)
You could also use a Raspberry Pi Zero W