It’s your choice. The V2 hub is not a thread border router, so if you want to use matter-certified thread devices you would have to have at least one of those, but there are going to be quite a few choices, including some Apple devices, some Google home devices, and some Amazon echo devices. Or the new smartthings “station” matter hub.
The V2 has more memory than the V3, which can be useful with edge drivers.
And if you did get rid of your V2, you would have to rebuild your entire Network, and all your automations for any hub connected devices.
So if it was me, personally, I would keep the v2 for now. But different things will work for different people.
The following thread might also be of interest: