This is anecdote, not proper feedback, since I wasn't directly involved in the topic.

My company relied on PG as its search engine and everything went well from POC to production. After a few years of production and new clients requiring volumes of data an order of magnitude above our comfort zone, things went south pretty fast.

Not many months later but many sweaty weeks of engineering after, we switched to ES and we're not looking back.

tl;dr; even with great DB engineers (which we had), I'd suggest that scale is a strong limiting factor on this feature.