Your opinion is based on endless growth. That's a fantasy, there's no such thing. We cannot continue operating in the red, extractinf but never giving back.
A declining population and slowing things down is not a bad thing. That's actually what we and the planet need. We need to buy ourselves time. If the choices are choosing degrowth and a bottleneck? Duh. Degrowth. It's degrowth. Every time.
You're missing the inescapable fact that that's our choice. One way or another, the population is going to decline. That's baked in now. It's going to hurt.
The question is whether or not we make that decline an E.L.E. by continuing to irresponsibly pursue the fantasy of endless growth.