If you have the Ethernet cabling, use that. Wired is the better way to do it in almost all scenarios (only one I can think of that is not is if there is improperly/outdated wiring). In any case, you wanted benefits (assuming proper cat5e/6 or higher wiring):
1) Almost no chance of interference.
2) Better bandwidth in general.
3) More bandwidth available for devices USING the wireless (not the routers talking).
4) Security, requires physical access to a port.
5) Point to point communication.
There are more. I know you did nit ask, but many people might want disadvantages also but mostly they apply if you do not have the wiring.
1) Expense
2) Difficulty of installation especially in existing spaces
For an example article:
www.howtogeek.com/217463/wi-fi-vs.-ethernet-how-much-better-is-a-wired-connection/