Is it time to upgrade?

What are you primarily using the machine for? If you're using it for work like photography and video work such as Affinity Photo/designer/publisher or Adobe CC, those are long in the tooth, to the point they're beginning to show their age. You may consider an upgrade, but a better SSD (Apple OEM or a compatible SSD that doesn't need to be adapted) like this may help you get a bit more life out of it, but it may not be much.

If you use it for less intensive work, slap an SSD in it, and you'll easily get a few more years out of it. There is no need to upgrade unless you want a machine that isn't a pig in terms of power consumption, given that the Xeon processors were always known for being heavy on power consumption—sometimes as much as a laser printer in a dual Xeon setup with a professional grade GPU like a Radeon Pro/FirePro or Quadro!

I have a 2013 Trash Can and it’s still holding up! Sure the system is limited with a peg leg GPU as the dual GPU setup never caught on. Even still the one GPU wasn’t bad!

Your work flow and needs is how I look at this. Having the fastest car won’t help you in stop and go traffics, and in the same light the time of processing you are doing on your system is how you need to look at and if it’s time to upgrade.