It is quite strange that you have already discerned the entire plot when the story hasn't even told us anything remotely sexual about either character. While it is highly likely the prince will be submissive, who's to say the big guy doesn't like having his ponytail grabbed while having his cheeks clapped? At the end of the day it is the story that the dev wants to tell! Nothing wrong with constructive criticism but simply venting crap like I won't read it bcuz you're not making the character a top isn't remotely constructive!
One of the best VNs I've read is Remember the Flowers and admittedly I was apprehensive about reading it the second it announced the MC was asexual but I gave it a shot and they did not disappoint. I didn't attack the dev for not making the character I wanted. I took it as the story the dev wanted to tell.
Often times these stories are influenced by the patrons anyway. Many devs have polls which allow their supporters to influence things in the story. You're scrutinizing a project you've contributed $0 towards like they charged you for it, Karen! Being dominant might get you what you want in bed(doubtful 😑) but at the end of the day it is probably 80% boss bottom bitches paying the $5 or $10 subs.
You needn't respond to this by the way. I have no patreon account that requires your coin and your opinion means far less than that to me. This post, as yours was, is just meaningless thoughts spoken to express my distaste of your idea that this world or any other would cater to such a person as you. I'll even assist your cause and make your lil ego feel a whole 4 inches tall by giving this comment it's first dislike 😋. Aren't I the sweetest?