What is the best argument for switching from PoW to PoS?

So I've been buying ETH for a few months now, and I really do like the technology. I am however very concerned about the idea of switching to proof of stake. I have done some research but as of now haven't seen any good reasoning at all other than "it's good for the environment". Clearly PoS would consume less electricity, but that is totally irrelevant to the reason one would invest in Eth. People want a dependable, secure, reliable system to protect their investment. Saving energy as an excuse to make the system objectively less secure doesn't make any sense to me. The entire purpose of the bitcoin PoW system is that miners are investing in energy and converting that energy directly into bitcoin. The electricity used to mine bitcoin is actually creating bitcoin and storing energy in the coin itself. Time is money and money is store of energy + work in the end.

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I'm not here to shit on ETH, clearly as I am a holder myself. I just would like to hear the best reasons for why PoW to PoS is a good idea. It seems like almost entirely downside in my personal opinion. Under what circumstance is PoS even remotely as secure as PoW?