When it comes to questions like this, I think a lot of it comes down to what you plan on doing with the device. I have a Go 2 with the M3 processor and, personally, I think the processor has held up better than I thought it would. That said, I don't do anything that's truly CPU/GPU intensive (in fact, most people don't).
I mainly use it for Office/Google Docs, web browsing, some light video editing (Premiere Elements 2020), photo editing (Affinity Photo), xCloud, and a handful of work applications like TeamViewer. I'm actually using it as my main computer now because of how light and portable it is. And when I'm at home, I have it connected to a 1440p monitor. I'm very content with it and have no reason to upgrade.
Buuuuut.... I've had mine since launch and Microsoft is still selling it for $630 for really outdated specs. I can't say for certain that a Go 3 is coming this fall, but it's highly likely that new OEM tablets are coming this year with the launch of Windows 11. And given how far processors I've come since the M3, all of them will dwarf the Go 2 in power.
If you have the opportunity to get one for cheap, I say go for it. Otherwise, you might be better off waiting to see what is available this fall.