i'm a hobbyist woodworker with more money than time. i have a pretty basic 3-axis cnc and i thought it would save me time, but it really doesn't. the only thing i actually use it for is cutting out router templates, and even that would be done better with a laser cutter (although a good laser cutter costs a lot more than my cnc).
i could see how a machine big enough for 4x8 sheets with an automatic tool changer, a vacuum table, and all the automatic calibration gizmos might be a time saver for a production shop, but if you're building something that's a one-off or you don't have all the setup automation goodies (which are $$$$$) then setup and programming usually end up taking longer than doing the work the old fashioned way.
for tenon cutting like in the bed rail example you gave, i have a hard time imagining any situation where cnc is going to be more efficient than a domino xl.
I find CNC is a time-saver for one-offs when the work is complex enough that it'd be difficult-to-impossible to do by hand, eg complex curving cuts, engraving/pockets, etc.
I actually saw an unusually straightforward example of this last year - a group of friends and I were making instances of Tyler Gibson's 1-sheet portable bike rack design (it's great, check it out: https://www.thetylergibson.com/building-a-better-portable-bi... )
One group of two-ish people used jigsaws to manually cut the pieces, and I used a Shopbot 4'x8' CNC router. Very roughly, it took about twice as many man-hours to make one by hand, vs by CNC, and the result was less clean. CNC could have done even better, but due to warping of the sheet, it failed to cut all the way through in places, and I had to do a cleanup pass with the jigsaw. And once the upfront cost of generating the toolpaths etc was paid, it would improve again.
4x8 CNCs with a vacuum table really aren't faster. Even the watercooled CNCs I've used are still too slow for joinery. All the furniture shops I've worked in have been dominated by the Domino for most joinery tasks.
i could see how a machine big enough for 4x8 sheets with an automatic tool changer, a vacuum table, and all the automatic calibration gizmos might be a time saver for a production shop, but if you're building something that's a one-off or you don't have all the setup automation goodies (which are $$$$$) then setup and programming usually end up taking longer than doing the work the old fashioned way.
for tenon cutting like in the bed rail example you gave, i have a hard time imagining any situation where cnc is going to be more efficient than a domino xl.