Pushing legalities and other issues aside, I actually believe it won't be too long before we get some type of 'console' that will actually be able to play all console games, no matter the format, from past generations. Hell, we already have the likes of Retron5 and the Blaze Tab, and just recently Nintendo jumped on board this bandwagon with the release, albeit short-lived, of the NES Classic. Apart from the 'I'm lazy so want access to every game ever made all in one place without having to move or change a disc', why does such a thing even need to exist beside what we actually have readily available already? For starters, the vast majority of us have a decent enough PC capable of playing ROM's, and even if not, there's consoles already on the market that cost peanuts and can be modded to allow use of emulators...I went out and recently bought a Wii just for the sake of Letterbombing it and having a sh*t ton of old games playable.
The fact you mention about having friends lists and online co-op totally abolishes the nostalgia for me. Playing Mario Kart 8 online just doesn't have the same affect as what having 4/5/6 friends all huddled around a TV in a Battle Tournament on MK64...Hell, call me old fashioned but even the likes of Battlefield and CoD just don't have the same what-have-you as the days of having a group of you battling it out on Goldeneye. On the flip side though, the one thing I do like of online MP is having leaderboards and grinding away to beat all your friends scores/times etc, so I do agree with you on that point I suppose.
Putting all that aside, on the whole, I agree with your whole subject matter, and have posted multiple topics on this forum alone about how my interest in modern gaming has declined majorly, and how it has very little to do with me getting old, and more just the gaming industry as a whole. I remember been really hyped about the 360 before it was released, and due to been in a bad situation I wasn't able to pick one up for a few years, but I was glad for this because it let me sit back and see how the console was fairing and how the games reviewed...and when I finally had the money to spare I ran out and bought one with a sh*t ton of games and loved it...fast forward a fair few years to the One/PS4 and I literally had very little interest whatsoever in either of the 2 consoles, and even to this day I couldn't care less, only wanting one when they reach a cheap price just to pick the odd game up that has peaked interest, and even these don't happen to be any major AAA title...Simply put, the majority of these AAA titles suck IMO, and have become so majorly generic and repetitive that I find them pointless.
Funnily enough, the games that are peaking my interest so far are HD remasters and the like, like the Crash Bandicoot HD Trilogy and the Rare Replay collection. As you said though, the money to be made from these is very little, as it only applies to a very select audience, of which will get smaller as the years go on for obvious reasons. The youth of today won't find the fun in something so simplistic as the games of generations gone by.
The amount of money I've spent recently on 'retro gaming' could have easily bought me a PS4/One and plenty of titles, but I just couldn't care less. I have my consoles split up into 2 rooms in my house; Switch, PS3, 360 downstairs - PS2, Gamecube, Wii, N64 upstairs in a spare room...and guess what, I spend more time in my spare room playing all my older titles, even though my 360 collection is the biggest by far. I get more pleasure from the older games than I do newer ones, for so many reasons - One been the fact that technology was (in a way) limited back then that games had to be enjoyable, and with no DLC and sh*t like that, they had to be REALLY good to make profit, and that's why older titles rate higher than newer, modern titles IMO. The last few new titles that I bought for my 360 were major letdowns for me, and dissapointed me to the extent of declining my interest in modern games. GTAV was one of the recent, newer, titles and look at what a flop that was, only going to prove how the Cash Cow of Online Gaming is the priority these days; Hell, CoD was been released for the 360/PS3 as a MP game only, that in a few years will be totally non-playable and only worth binning...All for the same price as other games on the market. Games are been released as part-titles and the other content has to be purchased afterwards. Games are bug-ridden messes because they have to be rushed out due to the market.
To add another point to your post Daz, it may mean little to you (genuinely no idea, this isn't an insinuation), but nothing beats having shelves full of old titles in their cases, the artwork on each of these cases with the descriptions on the back, only to open each case and have a game manual to read through too. Digital titles will never, ever come close to this, no matter how little price is for the content you get.
I had a point when I started this post but I think I've just rambled incoherent sentences...Main point is, yes, Retro gaming beats modern gaming by a landslide, but any attempt to recreate the experience by other means doesn't come close to having the real thing.