I would definitely say dumbbells aren't very viable for a home gym. What I mean by this is that they are stupid expensive and you're not going to be able to get a range of dumbbells without blowing tons of cash on them. Having a few sets for different stuff is fine. Home gym stuff is pretty obvious:
What you easily should have: Squat/Power rack, barbell, 300-500 lbs of plates, pull-up bar/dip-bar attachments on to rack or something, some dumbbells and bands and shit.
What I have: 2 barbells, 1 trap-bar, 500+ lbs of plates, 10s-20s-35s dumbbells, two 2.5 inch dumbbell bars (just put plates on them mini barbells essentially, adjustable). I have a shitty but low-key solid Gold's gym bench/squat stand/preacher curl-leg extension-hamstring curl combo. A pull up-bar / dip-bar tower thing, multiple bands, e-z curl bar, neck harness, CoC #1, forearm rollers with plate load, grip gear (pinch block, and other bullshit), shitty heavy bag thing, 25lb kettlebell, foam roller + lacrosse balls, dip belt to add weight, 20lb vest never use it, used to have a prowler sled too - barely used it,
I listed a ton of shit and my takeaway would be this: You don't need it. You don't need all the dumbshit, TS you listed a bunch of retarded stuff at the end and overall. You don't need a fucking treadmill for a homegym, you don't need a cable fly machine lol, or hamstring curl, and the adjustable dumbbells suck...what I have is way better the 2.5 inch plate loaded ones, and cheaper. Just get them on amazon, CAP - not the best quality but they work, they are just hunks of metal.
To be more succinct basically my opinion of the home-gym tiers would be this:
Tier 1: Power-rack (or squat if $ is an issue), barbell, trap-bar (imo), decent plates up to 400 lbs minimum (to start), Pull-up bar attachment to rack, bands for prehab/rehab/rotator cuff work. At least one functional set of dumbbells / kettlebell. Foam roller + lacrosse ball shit.
Tier 2: Adjustable DBs - the loadable plate one, dip-bar if possible, Safety Squat bar (if needed/preferred at all).
Tier 3: Neck harness, forearm/grip equipment, dip-belt to add load pull-ups / dips once you progress, more specialized band shit probably, ez curl bar and specialty bars.
Tier 4: Only you have space and money then you go for the heavy bag / specialized equipment such as a glute-ham raise or an inversion table or the more exotic shit.
TLDR: Power/Squat rack, barbell, plates. Bingo. That's the core. Then I would say it's essential to get the dirt cheap shit like bands, foam roller, lacrosse ball for prehab/rehab stuff too, would be dumb not to get it for 20-50 dollars max.