No harm is really done?
As a former youth minister who witnessed such ostensibly harmless sexual behavior, I know that to be a fatuous lie. PERIOD!
Let’s see the possibilities: Unwanted pregnancy. Sexually-transmitted disease. Public embarrassment (or humiliation, depending upon the sub-culture). Destruction of parent-child trust. Erosion of self control and self esteem. Gateway to other moral/ethical corruption.
Yeah, tell those jurors it’s all a-okay, and this is the modern day, and parental authority is so 20th Century. Mustn’t discourage horny lads from exploiting naive and vulnerable female legal minors!
One may - may! - argue that the degree of harm is lessened, but it is manifestly there.
We do not have an agrarian society, where 16-year-olds can legitimately marry and set up a household together on a farm and be independent and productive and treated as adults by their fellows.
Federal control of education makes high school attendance -and hence functional adolescence - artificially extended to age 18, the age of legal majority, regardless of biological urges.
Yes, it is somewhat arbitrary, but it reflects that the 17-year-old (usually the female) is still wholly dependent upon the parents who are legally responsible, and must therefore also have their authority protected by law; the 19-year-old (usually the male) is almost never either able or willing to be wholly responsible for the female he is using for his transitory pleasure.
Trivializing this scenario via the 17 & 19 situation plays into the slippery slope that the communists want society to slide down.
The legislature of the State of Maryland does not. Do you want juries "convicting" people of "crimes" that they have just invented, because they think the relevant legislative body got it wrong?