I think it's a natural course in most instances for one person to love more than the other person (whether monogamous or polyamorous). Or at least it easier for one person to show and express that love more easily. One seems to always give a bit more than the other (sometimes quite more than a bit). One is usually more secure than the other.
This is along the lines of what I think about when someone is against intergenerational relationships between adults, whether consanguineous or not. The excuse used to object to someone else finding love is that there is a difference in power and life experiences. But there are very few, if any, relationships where that isn't a reality. One person usually has seen more of the world than the other, or has better emotional coping skills, or more money, or more friends, or more family, or more status, or any number of other traits or resources.
Polyamory requires some sense of self worth. It requires not having the mentality of win-lose situation. It requires the ability to see a win-win situation. It means not seeing other relationships your loved one may have as competition.
Ding ding ding!
If you realize that you are not fine with what you stated, there is nothing wrong with explaining this to your partner and dealing with it from there. You have to own that you have a part in the pain or issues you are experiencing. That you can’t do blame if your partner was told this was ok.
Feelings may change over time, and it is okay to talk about that.
In all relationships in your life you need to treat each other with the respect and dignity that we are all due. Most specifically from those we trust with our feelings. With those we love and who profess to love us.
Good words to keep in mind.