I don't get the hate for the Domino. It is an extremely useful tool to save time, but it is a purely luxury thing and there is nothing that you can't do without it. After all, in the end a Domino is just a fancy dowel and you can build anything that is shown in those youtube videos with a cheap dowel-jig. I built complete tables with this jig: https://www.youtube.com/watch?v=osC9T3WVnlM which cost me 20€ in a set with dowels, drillbits and woodglue. Yes, it took me 2 hours to do the dowelling which would have been 15 minutes with the Domino, but I am only building a table once every 10 years and not weekly like those Youtubers do.
My main gripe is that you can't roll one out without excusing yourself from using it. So you hear "Yes today I am using a Domino, but you don't have to. I get lots of comments saying "Well that's great if you have $90,000 worth of tools" You could do this with biscuits or dowels, or make the mortises with a normal router, you don't need this thing, but since I do have one..." And I'm kinda tired of skipping through it.
But it speaks more to OP's overall gripe, where woodtubers will start a video with the thesis statement "I made this in an afternoon out of just one 2x10!" Actual materials list: 1 2x10, two board feet of white oak and half a board foot of walnut "I had lying around," four hanger bolts, four lag bolts, two pairs of self-closing drawer slides, four locking casters, and nine nails. Add on to this several large pieces of plywood, pine and toggle clamps for making specialized jigs. Several steps use a jointer, planer, drill press and other large, expensive tools hobbyists likely don't have. The joinery process takes no time at all because of the use of a $1500 joiner.
"And that's how I turned a single 2x10 into a luxury camping trailer that sleeps six, all before dinner time!"
They sell it as a cheap and fast project, except during the course of the video the budget balloons into the tens of thousands when you include the tools. Sure you could get it done with a simpler set of more basic, multifunctional tools...it'll just take forty times longer.
I think it's a pretty natural tool to "grime" on, here's why:
The Domino is uniquely able to make a project easy and fast, but is pretty much inaccessible to beginners. A job that can be done in a few minutes with a Domino takes a few hours making mortises by other means, or using dowels, and all those other means take more skill to use than a Domino, which is as easy to use as a biscuit joiner. And there's no home gamer version.
When I see a Woodtuber pull out a track saw, I can translate that to "my circular saw and my straight edge clamp. Got it." When they pull out a spindle sander, I say "sanding drum in my drill press. Got it." When they pull out a Domino, I go "...decide which of a few other joinery systems are available to me, possibly redesign this part of the project to fit these new limitations, spend a lot more time laying it out and setting it up, then carefully make a plunge cut with a router or use a dowel jig. Got it."
Some woodtubers don't ask themselves "is this a beginner project with common general purpose tools, or is it only quick and easy because I have expensive specialized tools?"
If the projects shown would use a dowel jig, you would only get one video per month from your favorite channel instead of one per week. Additionally, it would be extremely uninteresting to watch the YouTuber use the dowel jig after the first 2 videos you watch because it is tedious and not very interesting.
And I really dont see the point. As a hobby woodworker you would be able to complete the projects with the same result by using a dowel jig, it would just be more work for you. When they say "I use the Domino because I have it on hand, but you can use any tool that you own to join these boards" that really is true. The Domino does not change the outcome, it just makes the process easier.
I didn't think there's anything wrong with using a domino. Not every channel explains that you can use a dowel jig.
A real problem in DIY video is treating materials cost as the only cost to taking on a project. I've definitely seen at a bunch of them demonstrate doing a project in a way that requires a certain tool without explaining alternatives. I've seen many videos that get a job done for under 50 dollars because they have a full shop on hand.
Ahh, okay yeah I get it. Would be a lot better for beginners if they just said "I'm going to use a Domino, if you don't own one you can use a dowel jig. Here is a video explaining how to do it" and link to a dowel jig tutorial. Would probably be the best for new watchers and doesn't annoy the long term viewers who know how to use dowels