You are going to be looking at some variant of oculink, you can get riser cards that convert a PCI-e or M.2 socket into an oculink port if you don’t have one available stock. Still though, if you are building it yourself why even bother? You are going to add a significant cost to the build for marginal or no benefit over buying a mini PC with an oculink port and a known compatible dock. EGPU options are not plug and play, they rarely just work and need significant tinkering and workarounds and will come with noticeable drawbacks in the best case scenario.
I watch his videos from time to time, he stays quite up to date when it comes to the underpinnings of modern software engineering. Mind you, just because he retired doesn’t mean he stopped tinkering and building. By all accounts he is still poking around in a number of projects and contributes his fair share of expertise. I’m not a fan of him not outright calling out Microsoft for their bullshit, but I do respect the sheer amount of expertise he brings to the table. Calling him out of date, particularly with the level of understanding needed to make something like a task manager, doesn’t seem fair.