Yep. Lots of people (but maybe not as many as might be thought) need to step down their relentless wasteful consumption. We don't need to return to mediaeval levels, but something akin to a Costa Rican, or south Indian, median standard of living.
People used to laugh at me 25 years ago for using a home-made fabric shopping bag, but maybe I was just ahead of the game! I don't know if it's just me but seeing stuff like the overblown luxury of Dubai, or the pointlessness of Formula 1 racing (using fossil fuels), or sandwiches sold in plastic boxes just makes me feel ill and guilty on their behalf.
The world's population is forecast to stabilise at around 10-13 billion within the next 100 years, then gradually fall. The main 'boom' in world population currently taking place is down to improved healthcare and not extra or multiple births [ie., folks are sticking around a lot longer] The global average birthrate per woman is almost down to 2 (replacement level), and then predicted to fall further. See
https://en.wikipedia.org/wiki/Total_fertility_rate for the figures
Some nations are already seeing marked birthrate decrease (eg., Italy, Japan, Korea to name a few).
As education and information spreads, family sizes fall and there's some room for optimism here. The main issues facing us all in the 'first world' are how to care for elderly people compassionately when they are in the majority (Japan is already facing this demographic conundrum:
https://en.wikipedia.org/wiki/Aging_of_Japan ) AND how to suppress the model of a constantly expanding economy and shift it into something much less wasteful and damaging.
It's not impossible that a pandemic will get some of us, leaving only the fittest, but the predictions of doom are a bit overblown. Each one of us that turns their back on rampant consumerism and waste is doing their bit, however small it may seem. We have that power! If the billionaire class wishes to zoom off to another planet and consume that, too, then let them.