Ideally, we do some research before we get animals, so we know what we are getting into . . . .

A lot of people jump right in without, but sometimes, even if we do it, we later learn that what we were told or thought we already knew was either wrong, or wasn't nearly enough.
I got into rabbits over 30 years ago, with what were meant to be just pets. Even with my research, my very first pair of rabbits, which I thought were two does, turned out to be a buck and a doe. Fortunately for me, I learned of my mistake before they were old enough to breed (and, having seen very experienced rabbit breeders accidentally entering junior bucks in junior doe classes, I can tell you it's a very common and persistent mistake!). Sadly, an awful lot of people find out the hard way - dead babies. It happens. A
lot.
So, now you know, and feel the need to do a bit more research. Hopefully you will learn things that are useful and help to make your rabbit keeping a pleasant experience!
(Incidentally, I have a real problem with that breeder's statement that his rabbits' babies just stay in the mothers' nests. Baby rabbits are highly mobile, and can crawl around a lot before their eyes open. Being born without fur, they need the nest and each other to stay warm, but they can hang on when the doe leaves the nest and get pulled out. If they don't happen to crawl in the right direction, they can wind up a long, long way from the nest, and die of exposure (rather quickly, during cool weather). During hot weather, the babies may overheat in the nest and crawl away from each other, once again resulting in possibly lost and dead babies. The domestic rabbit's wild ancestors dig burrows, so the babies are born at the lowest end of a tunnel - much harder for them to get lost that way, plus protection from weather extremes. Unless the breeder's does are digging tunnels, and even if they are, I suspect he's losing a lot of babies that he may not even know about).