IMHO
Pegging gets you ready to take a real guy. I did this with my husband. I pegged him even before we were married. After we were married, I wanted to see him with a guy. He was reluctant for sure. First it was a bj and he did fine. He was hard the whole time. So, he's just hesitant.
Pegging is similar to a guy because if you are a bottom, you have to do it until he/she is done. I'm the same way. My husband has to take it until I cum once, twice, and sometimes 3 times.
At one point, I actually asked him to let a real guy fuck him. The reluctance became even stronger. I eventually convinced him. I knew one of the blk guys I was with did allow a cuck to give him a bj. So, I asked him, he agreed since he likes us.
With reluctance, my husband did it.
Our guy was not as big as the OP, but still good
My husband said it was like pegging, but was different when our guy came in my husband. OMG, I did love the look on my husband's face when our guy started to cum inside him. It made all the effort so worth it.
So, if you get pegged, you can maybe be a bottom for a real guy. It's happened.