FCO Rome to Sorrento is there an easier way than the train?

I've been looking at in reverse and at best in June I'm finding prices of around $350 Euros.

That was me —we used them for Naples to Sorrento then from Sorrento to Amalfi
Very satisfied

If your budget doesn’t allow for the full route from FCO then the transfer from Naples to Sorrento is nice, we paid 90 euros 2019

It is really not that hard to take the train from Rome to Sorrento transferring in Naples. We actually used the Campania Express to get from Naples to Sorrento, which is a private tourist train that runs from Mid-March thru October with less stops that the regional train, is much less crowded and air conditioned. The station is on the lower level of the Naples Centrale station and we purchased the tickets at the window about 30 min before or you can pre-purchase on the website. About 15 min before departure these two uniformed ladies (with little hats) stood by the gates to greet us, once all the passengers were there we were guided by them to the Bin, which had benches for us to sit on and then they boarded us, making sure only people with tickets got on (others tried to get on at that terminal and at the Pompeii stop). The actual inside of the train was nothing special.
We actually used the time between the two trains to grab some Pizza at da Michele, which was an experience in itself.
You can also hire a private driver, we used the company Amalfi Coast Destination for an all day Amalfi Coast tour and my friend used them for a transfer from Rome to Sorrento. Not sure on the price but you can inquire.
https://www.amalficoastdestination.com/item/private-transfers-en/amalfi-coast/

Campania Express:
https://www.sorrentoinsider.com/en/campania-express-train-schedule

Waiting at each station for the next train wastes a lot of time.

There is a tran from FCO to Rome every 30 minutes, one from Rome to Naples every 45 and the Circumvesuviana to Sorrento is basically a metro line running overground. What site are you using to plan your journey?

I thought the sequence of trains from Rome to Naples to Sorrento was about as easy and efficient as it could get. Sure, the circumvesuviano wasn't very pretty, but other than that (and the risk of pickpocketing, which is present all over Europe), it was cheap, efficient, easy, pleasant enough, and I'd do it again without any concerns. It's a long way to go if you are going to spend money for a private driver...I'd save that money for a nice splurge dinner in Sorrento.