Ultimately, I think the D&D game needs a ranger. Cutting it out, and replacing with a background, just wouldn't fit in the game. It's core to the game... in the same vein that you can't really do a Dark Sun game without making sure you've got "templar", "Defiler", and "Gladiator" available as class options.
Now, do I think that the 5e ranger is kind of weak? Yeah, I really do. And I don't mean "Weak" as in "Underpowered", I mean "Weak" as in "it really doesn't jump off the page like the other classes do".
The problem is that unlike pretty much every other class in the game, the idea of what MAKES a ranger seems to change every edition. We've always known that rogues are good at skills and striking from surprise. Fighters can take and deal damage and wear armour. Wizards cast spells.
But rangers? Well, sometimes they're good at skills, other times, not so much. They wear light armour... or heavy armour, depending on edition. Sometimes they get animal companions, othertimes, they don't. In 1e, they got both wizard and druid spells. in 2e, they got neither... but instead got a few cleric spells. In 1e, they were great at killing giants... in 2e, that kind of changed, and they suddenly became dual-wielders.
And so on, and so forth.
Because of that, saying "ranger is a background" now doesn't make sense, because you're running into the same problem.
I think if we got rid of legacy issues, and looked at the ranger class as it currently stands, but named it something else ("Scout"?), fan response to it might change.