It always amuses me that bunches of players for some reason keep wanting to condense the game rules down into like three or four small buckets. "Merge the classes!" they say. But it's like "That's why the Basic Rules were for!" for 5E14. If you only want four classes... you had them right there at hand. But apparently that's not good enough for them, they need the entire full game squished down for everybody. Why is that? Is it because they are just unwilling to stand up to their players and tell them the game will only use the Core Four classes, and instead want the book's design to make that declaration for them? Because they don't have the guts to declare it themselves?
Anyone who wants to "get rid of" the Wizard / Sorcerer / Warlock (or Ranger, Paladin etc. etc. etc.) can do it and has been able to do it this entire time for decades. And if you haven't done it, it means either you don't actually care that much about it (which is why no one has taken your decrees seriously) or you know that none of your current players will go along with it because it's just not a fun or interesting idea and you're unwilling to take the time to find the people who will play the game in the manner you want. You want the Wizard, Sorcerer, and Warlock merged? Do it yourself and then find like-minded players to play that game you've created. You've had over a decade to do that for 5E alone.
Anyone who wants to "get rid of" the Wizard / Sorcerer / Warlock (or Ranger, Paladin etc. etc. etc.) can do it and has been able to do it this entire time for decades. And if you haven't done it, it means either you don't actually care that much about it (which is why no one has taken your decrees seriously) or you know that none of your current players will go along with it because it's just not a fun or interesting idea and you're unwilling to take the time to find the people who will play the game in the manner you want. You want the Wizard, Sorcerer, and Warlock merged? Do it yourself and then find like-minded players to play that game you've created. You've had over a decade to do that for 5E alone.