We may be the products of gene level selection but we are under no obligations to play by their rules.
One important distinction needs to be made between short term and long term mating strategies. In the short term men tend to lower their standards, women tend to raise theirs (this insight angers a lot of people but its obviously true, and the cause of a lot of human unhappiness. Sorry to be blunt but its time people stopped living in cloud cuckoo land over this)
That's what Cardi B and Megan Thee Stallion are singing about here. A sort of "You have to be X tall to get on this ride" sort of song...
But you have a long term partner. The rules are different. You can adapt to one another.
I'm not a sex therapist, and I wouldn't give out sex advice on the net if I were, but there are some things to consider.
As Carol Tavris quotes approvingly, "Sex is not soccer, the use of hands is permitted". But it's more fixable than that.
Plenty of couples have highly satisfying penetrative sex in absence of large penises or penises at all. Let me give you some examples:
In our studies we found copious use of insertables (e.g. strapons) by lesbian couples, and the gay male community also does a roaring trade in prosthetics that never get tired, soft or small.
There have been studies of couples were the male has micro-penis (through Kleinfelter syndrome or similar) where the female partner reports higher than average sexual satisfaction due to the extra effort (and possibly use of prosthetics) by the male partner.
In short--don't be taken in by others attempts to put you down, you are under no obligation to play by their rules (and there's a lot of lying going on in any case).
Yes--it seems clear that human penises are under sexual selection, but so what? Anyone can learn to be in synch with what their partner wants. Communication is key. If it bothers you then just don't listen to any more tall stories.