Sure, you could buy an external GPU enclosure that would, in theory, allow you to upgrade to a newer desktop GPU, but then you'd be limited by the connection of the enclosure, which is still PCIe ...
External GPUs have been gaining in popularity ... A prime example of this is the GPD G1 which lets you plug a Radeon RX 7600M XT GPU into an enterprise notebook. At Computex 2024, Sparkle ...