There is no need to worry about the future of Bitcoin and Don't be discouraged by the issue even though PoS is considered more energy efficient, everything has been neatly structured by Satoshi, there is no reduction or increase in the supply anymore and only 21 million Bitcoins.
PoW can be as energy efficient as PoS. It all depends on what energy source miners use to sustain their operations. If the majority uses renewable energy, then there will be zero carbon emissions in the mining process. No need to switch to PoS. It's just that the term has been "politicized" to go along with governments' green energy agenda. Propaganda has made PoW look more energy intensive than PoS. But again, PoW can be made to consume less energy over time.
I'm not worried about the future of Bitcoin, assuming it continues to grow in mainstream adoption and popularity. It's been doing fine for the past 15 years. I'm confident it will do well another 10-20 years in the future. It might even survive way beyond the block halving event of 2140. If prices continue to rise, miners will be able to live off transaction fees. Neither you or I will be alive by the time that happens. Just sit back and relax.