The switch on its own will do nothing for you. It's only useful with a router that supports VLANs
Unfortunately in your situation you'll need to replace your current router-modem combo with a dedicated modem, a commercial router (if you don't want to build your own linux one then EdgeRouters seems pretty good value for money) and a managed switch.
If you want to keep it wired then you'll need to put it on a separate VLAN from your other devices. A VLAN effectively allows you to create separate ethernet networks over the same physical network. We use them at work to keep factory hardware separate from office hardware and I use them at home to keep a vpn open for streaming geolocked content from another country. Traffic between the two VLANs has to be routed just like it would if they were separate physical networks.
I have an Edgerouter POE which has a small built in switch and supports VLANs so I can easily dedicate a port on the switch to a particular VLAN. In my case I route that traffic through wireguard, but in your case all you really need is setting up NAT for internet access and not route it with your other VLAN.
Any commercial grade routers support VLANs, i've seen it on unifi, aruba and fortigate and have never heard of it not being supported.
As others have pointed out, if you have a switch between your TV and Router then that'll need to be a managed switch that can trunk the vlan code back to the router, otherwise all the traffic will be comingled.
Other thoughts:
You might be able to arrange your IPs to sort of fake it. If your router is 192.168.1.1 and you make the TV be 192.168.1.2. Then you could give your TV a static IP configuration and tell it that it's subnet mask is 255.255.255.252. Then it'd only consider the IPs 192.168.1.1-192.168.1.2 as being in it's local network and if it tries to access something else on the LAN then it'll send it to the router for forwarding.
I'm not sure what your router would do in that situation, but it seems unlikely it'd manage to forward that packet. You'd have to avoid putting any device on 192.168.1.3 (as that'd be the routers broadcast address) but I think you could probably make that work. It's not really secure (as anyone that compromises the TV could change the subnet) and it'd still be possible for devices on your network to send UDP packets (but not get replies from) the TV. It's also not really extendable and you probably can't get a second TV to work like that (and definitely not three), but it wouldn't require switching to commercial routers.
Slackware was my first distro too, probably around 95 i think as I got a CDR copy from a friend in high school. It's certainly not been my daily driver for that whole period, but I think I've probably at least had a linux system operational for nearly 30 years.
I've been using Windows since maybe 92 and MacOS since 86. I think Solaris is the only other OS I've used a significant amount. There days I've got a Macbook Pro for work, Windows 10 for photo editing and Kubuntu Jammy for everything else.
It is kind of a disaster for emergencies. Twitter is the defacto social network whenever any disaster strikes round here, the sheer volume of people, emergency services and the versatility of hashtags make it great for that.
Yeah absolutely, plus there's lots of space for new entrants with different ideas for what a hybrid platform might look like. Some of them will surely be terrible but maybe there's a magical do-it-all solution that we just haven't imagined yet.
Not having to recreate the community from scratch makes it so much easier for technologies to emerge
I'm also not sure the interface is quite right. There are maybe use cases where subscribing to a lemmy community or kbin magazine might make sense in Mastodon, but most of the time that feels like a weird use-case. It feels like I want to subscribe to my own feed of people who reply to me, then I could reply to them from Mastodon (except there's no real link between my identities, which is messy)
Can you enable multiple vlans?