I’m in the same boat. Finished my doctorate when I was 27, and my son was born when I was 30. He is will be turning 9 this December, and I will be turning 40 in February. If my son has a child in 7 years, something went way fugging wrong.
I know plenty of people who went to work right after HS and had kids. I feel like some of them were successful and are still enjoying nice lives with their families, but most of them turned out to be scumbags.
If my son was graduating HS this year, I think I would advise him to avoid marriage/kids until his late 20’s/early 30’s. He doesn’t have to go to college, but I would love for him to be able to enjoy his 20’s without any serious responsibilities/commitments. Travel...get laid a lot...get arrested a couple times. You know. Enjoy life!