You do realize that Bitcoin, and Monero are both Proof of Work hashing algorithms, so the 51% vulnerability are shared on both.
While it’s more plausible that a 51% attack could be achieved on Monero, the fact a incident similar to that with selfish mining has occurred, the devs have been considering different mechanisms to counter act both attacks.
But yes hash rate is probably Monero’s weak point primarily due to its algorithm being focused on CPU mineability but I think a strong coordination of the monero community could counteract that.
Clip link (tracking parameters removed):
https://youtu.be/ncPyMUfNyVMhttps://bitinfocharts.com/comparison/hashrate-btc-eth-xrp-zec-xmr-doge-ltc-bch-dash-etc.html#alltime