Original Xbox one (2014) internet issues even with wired connection

I have had this Xbox one since 2014 and recently (last few months) have experienced some issues with its internet. I have exclusively used it with a wired, ethernet connection and have been having a lot of glitchy internet issues when playing games like Rocket league. It'll say my ping is anywhere from 30-60, which should be completely fine, but it is very laggy at times and can become impossible to play with. Even when it says 30 ping it plays as if it were well over 120. The internet plan I pay for is said to be at 250 mbps, and I am the only device on the network most of the time when I am playing.

Some key things to know:

• Replaced ethernet cable twice
  
• Reset modem/router countless times
  
• Have to fully power down and unplug Xbox after every use due to space constraints
  

I guess my real question is: is this a hardware problem since the Xbox is very old? I am considering upgrading to the xbox series S, and am just nervous to pull the trigger on it in case the internet situation does not improve. If you have any other suggestions on things I could try, please let me know.

:)