Nobody is saying that. If the human race is ever wiped out, which is possible, it won't be because some of us choose not to have kids. There will always be a sufficient number of people who do want kids to propagate the species.
The interesting question to mull over is whether it would, or in fact could, be a 'bad' thing for the human race to no longer exist. Personally, I don't think it could be for the simple reason that 'good', 'bad', 'regret' etc are human constructs. Unless you're religious, 'good' and 'bad' exist only in the human mind and since nobody will be left if the human race dies out, 'good' and 'bad' will no longer exist either.
Coldel is right that the simple point is - if you want kids, have them and be happy. If you don't want them, ditto. I only get wound up by people who imply that those of who don't want them do really, but just haven't realised it yet.