Been using PHP for 20 years and have built multiple startups with it that went from ideas to exits.
Today's PHP is better than it has ever been. Are there some things that are rough around the edges? yes ofc. But there is no language that doesn't have that. It's all trade-offs.
Last week I switched from Nginx+FPM to FrankenPHP and my god even the deployment experience got 10x better.
Safe to say that if you haven't tried the language, give it a shot. Within a few days you'll know if it's a good fit for you or not!
FrankenPHP is really good but the reason perhaps PHP is left in the dust is that people reach for Typescript/Edge/Serverless hosts like Cloudflare
I personally blame Laravel for PHP's loss of relevance.