I’ve been ignoring the fact that there’s supposedly a newer version of SketchUp available so today I thought I would download and update. I am currently in Pro 2020 ver 20.2.172. When I check for update and select “Download Now” I go and select the SketchUp Pro 2020 file (Win 64 bit). The file is SketchUpPro-2020-2. Am I mistaken in thinking that my current version 20.2.172 is more current than 2020-2?
Yes. That message is telling you there’s a new version of SketchUp, not a newer version of SketchUp 2020. You’ve been ignoring the message telling you that SketchUp 2021 has been released. In fact you ignored it so long there’s even been a maintenance release of SU2021.
The current release is 2021. The 2020 version won’t receive updates anymore.
Major versions are…versions and within each major version there are updates.
You have the latest update for version 2020
Building on what @MikeWayzovski wrote, through all of its history, SketchUp has never released patches or minor updates except to the currently latest version. So, 2020 is now permanently frozen, and only 2021 will get any changes. When 2022 is released, 2021 will be frozen. In SketchUp land, “update” means “get the latest version”.