It's like DM Empowerment, but on the player side. If you have a 'modular' magic-using class that you build into something like a wizard, something like warlock, something like a sorcerer, or something else, entirely, you can create a mechanical model of whatever "where is all this power coming from" concept you come up with.
D&D's never done that, not even close (but closer than 5e, I suppose, a bit), but other systems have. FWIW, it's not a revolutionary idea.
D&D has been pretty firmly in the 'everyone who uses magic is essentially the same' camp for most of it's history. They all cast spells, from lists with some considerable overlap (more in 5e than in most, I think, and those spells all have casting times, three kinds of components, can (usually) be interrupted (or maybe counterspelled), dispelled, magic-resisted, possibly absorbed, etc... In 5e the full casters all cast have about the same slots/day chart, and MC casters use basically the same one, too.
And of course, all 5e casters cast spontaneously using slots, too.
I'm probably not explaining my thoughts very well.
I'm not saying it is revolutionary, I agree other games have done it, but I don't understand the inclination of combining them. It would be like the mystic.
Where the mystic (in its most recent UA iteration) got their powers from is completely up to the player, there are suggestions, but nothing really defines it. And the various sub-classes are highly unique while the whole is still incredibly modular to allow a full range of choice for the player.
And it works for me, but that is because psychics are not something that I see as close to the core of my game. Them being rounded up like they are is fine, because so very few players at my table would even consider playing one that the loss of identity from being combined into a single class is reversed by being the only Mystic at the table in usual circumstances.
But, Arcane magic and arcane practitioners are central to DnD, and they have always been relatively distinctive. We've had Bards being very difference from Wizards being very different from Sorcerers being very different from Arcane Archers and Theurges and on down the list for whatever list you would like to make.
And, there would be a loss in identity with the combination. Mechanically, I don't really care and mechanically it could work out, but let us assume that we rolled the Sorcerer into the Warlock, including all subclassses. We'd need to have a "source" which is a combination of all patrons and bloodlines (Chaos, Dragon, Storm, Stone, Pheonix, Sea, Shadow, Favored Soul, Fiend, Archfey, Raven Queen, Seeker, Hexblade, Great Old One) and then the "method" which is mainly warlock stuff (Tome, Chain, Blade, Bloodline, Seeker[they had their own one right?])
That is a lot of material to rewrite and combine, and it would come with all new mechanics, unless you made all sorcerers mechanically identical to warlocks or vice versa, and one of the two classes would not survive the combination. Then you have the issues involved with making some of the combinations fit. How did your Pact of the Chain make a binding deal for power from Chaos? How do you have a bloodline connected with the Raven Queen without it being an explicitly divine class and what is the difference between that and the Favored Soul? If you combine those two do you combine Stone, Storm, and Sea into Archfey? Being highly modular it is going to become difficult to ban or limit one or more of these so it may lead to just more bans of the entire new class.
And, you've gained what? Some more interesting mechanics for the Sorcerer potentially, but that doesn't require this combination. Just the ease of knowing that two concepts are now one? There is no new story here, no concept we couldn't work with before, I just don't see the point other than getting rid of the sorcerer. And if you want to get rid of the sorcerer.... just get rid of them. Again, it is a lot less work.
Other systems may have been built with a bunch of concepts swirled together. It may even work in DnD to a certain extent, but I think this is a bridge too far and would cause more loss of story potential than gain.