Is 16 and 21 an acceptable age gap?

I’m 21 and recently started dating someone who’s 16. She’s past the age of consent where we live, and both of our families know about us and are okay with it. We get along really well and have gotten pretty close, but I know the age difference might make some people uncomfortable. The gap is just under 5 years, so I’m curious what people honestly think. Is this age gap considered too much, or is it something that can work?