I’d go in but before I’d take a few seconds to:
Watch the swell and refractions to get an idea of depth.
Get enough clothes off to be able to swim efficiently.
Think about the temperature/risk of hydrocution and how long I’d have before being forced to give up and save myself.
Locate an exit point or somewhere to aim for with the victim.
Look for a float, even an empty coke bottle under your shirt makes a rescue easier and anything bigger is a big help.
Then just before jumping spot a few sighting points to go for while swimming to be certain of being on target for the victim.
All that might take 10 to 30 seconds but much improve chances of success and getting out alive. I’m a reasonable swimmer but lack the fat to be a good life saver.