It appears Facebook didn't make that decision, rather the market made that decision for them. Hence why the focus on Instagram and stealing Snapchat's schtick, to attract teens.
But no social media can currently compete with the force major that is TikTok, currently.
I read that Zuck actually saw the writing on the wall a few quarters back that his social media FB had peaked and would start to plateau/decline, hence the major investment into the metaverse pivot. It's a big bet and doesn't seem to be winning in the short term, but it's pretty strategic and smart of him all things considered.
Ultimately two things I consider that has me remaining bullish on FB/Meta:
1) Zuck is known to be a fantastic operator and is the only big tech* founder still in functional and practical control of his organization
2) Doing the painful pivot now: any pivot would always be hard and painful, but doing it now while still relevant and big (did 33bn in revenue last quarter) is smart.
*Is it fair to still call Facebook/Meta "Big Tech"? With the lost of $200bn in market value overnight, they are worth ~$670bn; all the other "Big Tech" (GOOG, AAPL, AMZN) all worth at least $1.4T.