The same is true in a big barrels. If a surfer knows they won't make it, they will pin drop and try to get as deep into the water as possible. If they fall and stay on the surface of the water in a big barrel they will probably be swept over the falls and be driven down with crazy force.
The buoyancy of a traditional life jackets wouldn't be good for surfers.
What big wave surfers use is inflatable vests with CO2 cartridges[1][2]. They pull a tab to inflate, and another one to deflate. They have multiple CO2 cartridges, sometimes surfers will have to inflate to get to the surface, take a breath, deflate and dive back under water for the next wave, then inflate again, until a jet ski can rescue them.
But inflatable vests aren't a thing normal surfers need, they are only for big waves in deep water (Mavericks, Jaws, etc.).
There are also impact vests and wetsuits[3][4] that provide a more passive form of flotation, enough to raise an unconscious surfer to the surface. These are used in big waves, including ones in shallow water (Teahupoo, Pipeline).
[1] https://www.quiksilver.com/highline-pro-airlift-vest/
[2] https://www.patagonia.com/psi-vest-purchasing/
[3] https://www.patagonia.com/product/mens-yulex-impact-wetsuit-...
[4] https://buellsurf.com/collections/job-collection/products/rb...