Re. La Paz - This is absolute nonsense. Many of the sailing community here are abandoning La Paz because of astronomical marina fees. There are boats for sale all over the place because fees are so high and they're rarely used. The only alternative to excessive marina costs is mooring on a sandy bottom with either no wind, or alternatively strong onshore winds.
There are many abandoned boats in the bay and on the shoreline, and the city doesn't pay to clear the wrecks away. Your information is about 10 years out of date.
In the last month I've seen quite literally a handful of people sailing with sails up. There's the usual half dozen gin palaces motoring to the beach and back, but that's not really sailing. If you'd been here you'd be aware there's hardly anyone sailing here these days. Additionally the few sail boats that arrive, stick around a day or so to load some stores and then get out of the place fast, realising that prices are so inflated and mooring in the marinas is either unavailable or excessively priced.
No. It's not a sailing paradise. It's a hole with a few soaks sitting in the marina getting hosed and bugger all to offer unless you're paying through the nose and flying back to San Diego on Monday morning.