The most closely related cryptocurrency that uses the same proof of work consensus mechanism as Bitcoin is BCH, which was forked from Bitcoin. For comparison, in terms of security, POW seems to be better, and also more demanding for cost operation and maintenance costs.
Unfortunately, BCH has never achieved the dominance its developers wanted to date. BCH was later cut off from Bitcoin in 2017.
If proof of stake were a more suitable option, Bitcoin wouldn't have had its consensus mechanism built around proof of work.
POW and POS are two different option, its not about which is better for Bitcoin. Bitcoin developers chose the POW mechanism. Technically, Bitcoin could be redesigned to use POS, but that's not an option cause miners will no longer benefit from the network.