Sit down sometime, make a realistic model of tidal power usage, and then figure out how long it’d before before ‘the moon being pushed away’ becomes visible. Once you can do that, then come back here and tell us about your calculations.

Of course the tides ‘rubbing against’ the Earth’s surface have been ‘pushing the moon away’ at a far, far greater rate for billions of years. Big deal.

That planetary core thing will probably be quite a way off, tho it last for millions of years. But the whole planet is swathed in tides, in-and-out.

Not sure on the numbers, but in videos I’ve seen dozens of places where -all- the local power cud be tidally-generated, and I suspect there’d be hundreds of places around the world. Largely depends on the geology around the local tides.