One of the main things that loyalty try to accomplish is to force Civs to expand organically, instead of settling all over the place with huge gaps between cities, aka forward settling. Disabling it in early game would go against the very reason loyalty exist in the first place.
Start the game with a scout, look for goody huts ,major civs, City-States, natural wonders. Build military early and hunt for barbarian outposts. Build a district with good adjacency if you got a good spot for it. It's impossible to get a dark age if you do that, and I'm not exaggerating, the chance of that happening is so low it's not even relevant. You're likely to get golden and pretty much guaranteed to get at least normal. If you're getting dark classical (or in any era, really), you're either doing it on purpose or doing something terribly wrong, like not even trying to figure out how to get era points and avoid a dark age.
As long as you settle your cities in a 9 tiles range of each other and invest on growth, loyalty isn't an issue. You can settle even in -20 loyalty tiles and still keep the city. If you gonna conquer or settle far of your cities, conquer/settle at least two cities in a 9 tiles range, so they can influence each other. Don't do that on a dark age, stick close to your own cities if you somehow manage to get one.
You can... you just need to raze stuff rather than keep it.
Razing is counterproductive as far as loyalty goes and the laziest way to "deal" with loyalty (you're not really dealing with it, you're running from the problem). You're deleting a source of loyalty and feeding a chain reaction where razing one city force you to raze the next because you never have loyalty. The main source of loyalty is population, from both the city itself and its neighbors, deleting the very thing that give you what you need doesn't make any sense. Instead of razing, conquer efficiently, plan your timing so a city don't stay for too long without getting influence from a neighbor. Conquer cities with high population first if possible, take down the capital soon if possible (pay attention on where is their second most populated city since it will become their new capital. Consider how that will affect you). Razing cities is never, ever something you should do to deal with loyalty, unless you actually want that city gone for whatever reason.