Sorrento a good base for the Amalfi Coast?

Yes.

Sorrento is not ON the Amalfi coast but because it is a transportation hub it is a good base.
Day trips to Pompeii, Naples, Capri are very easy from Sorrento.

If your trip is long enough you might consider 2 bases- 1 in Sorrento, the other ON the AC- Amalfi town was our choice (also a transportation hub)

We used this company for transfers in 2019
https://www.topexcursionsorrento.com/?portal_referer_id=46

Mondo Guides offers very affordable tours.
https://www.sharedtours.com

All are easy enough to do on your own though.

We did this:
Sorrento 4 nights
Driver to Amalfi- 2 nights then up to Ravello for 1 night
Ferry to Salerno 2 nights- visited Paestum from here- (then took train to Venice- Salerno is also a good base- direct trains north)

Do some searches here on forum, lots and lots of posts about visiting Sorrento and Amalfi Coast

You may find some of the links in the third post in this recent thread to be helpful:

https://community.ricksteves.com/travel-forum/italy/italy-help-with-orvieto-and-amalfi-from-paris

It is as good a base as any, in that you can get to Naples a couple ways, Pompeii, Herculaneum, to the Amalfi Coast, ferries to Capri, all pretty straight forward. But just keep in mind that travel is painfully slow in the area. The Circumvesuvia plods along a single route/ Ferries are infrequent and slow, buses can be slow and tangled in traffic, and driving not recommended. Basically you pretty much need to figure out a direction you will head and that is it for the day. You will not do the Amalfi coast and Pompeii or Capri in a day for example. Figure a day for the Amalfi coast, a Day for Pompeii and Naples (maybe a couple), a day for Capri, etc.

Sorrento also has a nice selection of restaurants, and a nice, but touristy, atmosphere.

Sorrento is pretty ideal for sights on the Bay of Naples (Pompeii/Naples/Capri.) It also has plenty of busses and ferries to the Amalfi Coast for day trips. The problem is, a huge chunk of the tourist crowd on the AC and Capri are day trippers. This makes a day trip a slog from my point of view (though many people do this and are fine with it.) Even with a private driver, the coast road can become an absolute parking lot at the end of the day.

Ideally, you would have a couple days in Sorrento for the Bay sights and then a couple days based ON the Amalfi Coast so you can enjoy your time there better.

Start watching the Nicki Positano vlog and watch older episodes as well for tips and views

Nothing beats actually staying on the Amalfi coast when all the day trippers are gone. We have stayed in both Ravello and Positano on 2 different trips and love the magic. Well worth the extra bucks.

We LOVE Sorrento, have stayed there many times, wouldn’t want to stay anywhere else. The AC is right around the corner and the geography is the same so it might as well be on the AC.

We stayed 4 nights in Sorrento in September. It is the perfect base for seeing the Amalfi Coast, Capri and Pompeii. We used Mondo Guides for tours of the Amalfi Coast and Capri, both of which were excellent and depart from Sorrento. We hired a RS endorsed private guide for Pompeii. It's a short train ride away, and our guide was waiting for us at the station when we arrived.

Sorrento is a joy, especially the Marina Grande. So glad we stayed there!