I largely agree.
Part A
The scale at any cost agenda is largely a concern troll, for people pushing various agendas -- usually hidden, sometimes at cross purposes with each other.
"Scale now, scale at any cost" is usually connected to a claim that by the time you hit bottlenecks it will be too late to fix, because there will be a phase transition from "bitcoin mostly usable most of the time" to "hardly anyone can open new lightning channels any of the time" and it could could happen in weeks, days, hours! (The "feepocalypse" it's been called.) That's pretty much hogwash in my view, and why I largely discount these scale at any cost concern trollers.
I don't think bitcoin will never need to scale, but I think you need it when you need it, and currently there aren't serious signs of danger. When bottlenecks do appear there will be a gradual ramp up in the severity and enough time to take appropriate action.
There's no crisis, and you shouldn't listen to people who say there is one, chicken littles.
That being said, all this research going into future scaling is great -- when there's no hidden agenda. But often there is.
So read stacker news, and don't feed the concern trolls.
Part B
But what about the part about bitcoin should be able to support everyone self custodying?
OK, this I completely disagree with, for the obvious reasons. Not everyone self custodies! If you are a scale at any coster, there will always be some justification for the fork du jour.
Bitcoin somehow now supports 8 billion people on chain? Oh no, but someday there will be 80 trillion AIs and also mind downloading with state cloning, all these sentient beings will also need to be open lightning channels. It's an emergency, We Need To Take Action Now!
Everyone relax.