My most recent ex was 16 years older than me.
I think if you're a practical person it can be difficult if you're honest about expectations.
If i am 50 and my partner is 66, that's going to be a huge difference in appearance. At 50, you could still probably date someone 30-40 if you take care of yourself, how is your 66 year old partner going to look to you when a cute 35 year old guy or girl is eyeing you at the gym. How much less are you going to be willing to put up with their bullshit when you are far less attracted to them physically?
I guess there is the "love conquers all" set but in my observations love might conquer a bit, but after a few years, a few decades, love gets boring as shit. Some people do better with boredom and routine than others. At that point i think it comes down to what type of person you are and what you value and believe.
I guess if you're the "true love" type, you might see the world one way. But if you are more cynical, it's easy to imagine if your partner was in your position, they'd leave you or cheat on you with some younger, it just so happens you are the younger partner.
So i think it comes down to an honest assessment about yourself. Relationships are hard even when two people are compatible.