It's not unusual for a player to switch numbers when he joins a new team.
If you shrink the parameters to only include veteran QBs who were previously MVP candidates on former SB teams, who are traded between the ages of 27 and 29 to a team where their previous number is already in use, who have more than three years left on their contract, were born in North Carolina but didn't attend a D1 college, then yeah, it's only happened to Carson Wentz. How rare!
This is called cherry picking.
Also, you didn't "simply" say it was unusual. You said more than that. And just like everyone else, you're entitled to your opinion, and you've stated that opinion. Now that I'm stating my disagreement with that opinion, you're acting like you don't really care. Instead, the problem is that I care about how much you care, and if I didn't care so much about how you care, the amount you care wouldn't be an issue. Have your opinion, state your opinion; don't be surprised when someone who disagrees decides to respond.