Even a 10 year old PC (assuming it wasn't low-end at time of purchase), with a SSD, is still good enough for most people.
For me, I'm planning on getting a Pixel 3a. The talk of it being like a "2 year old flagship" sounds great to me, not a detriment at all. I'm upgrading from a Honor 8, which is an almost 3 year old mid-range phone, so the Pixel 3a will be a decent upgrade, even though the performance of my Honor 8 is still perfectly good. I'm mainly upgrading for the camera, 3 years of software updates and because my Honor 8's Bluetooth is becoming less reliable over time.
The average user can comfortably use a 5 year old pc even today, ofcourse with an SSD upgrade.