Yep. This allows more deeper penetration and receivable positions for semen deposits.
Funny enough, there are rare circumstances where the arousal expands the cervix opening, allow penetration past the cervix sphincter to accommodate extremely long penises. This is partial penis captivus and vaginismus. One my my colleagues temporarily got into this predicament, where he was stuck with his partner for close to an hour or so, with the vaginal wall clamped down the moment he penetrates past her cervix sphincter. They had to take a dip in a cold pool for 20 minutes to relax their muscles enough and the vagina grip relaxed to allow his blood to move out the penis. So, be careful of how the brothers hammer deep into the pussy.