Theoretically, a simple switch could be more complex than it appears, and therefore theoretically it could have security issues.

For example, my completely wild guess would be that there’s probably an arm or a mips CPU and some ram inside that doesn’t really do much… this is because smart switches would often use the same switch chip, for Ethernet, but with additional flash chip actually populated on the same PCB causing some software to run in the thing allowing you to configure the device and giving the forwarding logic additional behavior.

Practically its extremely highly unlikely, that someone could exploit a dumb switch to run arbitrary code, regardless of the brand label on it and country of origin.

Enjoy the new switch!

Another option… How about a really long flat cat6 Ethernet cable?

… in 2023 no reason to separate…

Disagree heavily, (In cases when there’s no need for high performance devices to ever consider slower 2.4GHz g/n networks littered with 10year old iot stuff, they’ll still sometimes pick 2.4… and there’s usually no other way to configure this restriction on clients), … but that’s a bit of a longer discussion.

MoCA could be a nice hack if coax is there between floors and Ethernet isn’t.

Also, there’s “fancy” wifi client gear from Mikrotik in 50-100 bucks range, stick one end into Ethernet, point it towards the router and enjoy the +20dB of signal, as if the PC was in the same room.

(I apologize for using Mikrotik and fancy in the same sentence, but compared to most desktop adapters , the CLS of Mikrotik is kind of fancy, … I’m thinking of their sq5 series here in particular)

Too many variables in how WiFi can be set up, hard to tell.

Since you’re in a house, and I’m guessing in the US (mentions of microcenter), try the following:

• Separate 5GHz wifi network from 2.4GHz by giving them separate names.
• Set the channel on 5GHz to 36 or 149, instead of Auto.
• Set the channel on 2.4GHz to 1 or 6.

Then, stick to 5GHz on all devices that support it and where you have a choice, e.g. “forget network” the 2.4. …

… and see how that goes.

If you don’t need wifi, you could get a 1GB ram raspberry pi 4 + TP-Link USB dongle for a second 1GBps interface.

Can you be a bit more specific about what your needs are?