2018 has an interesting predicament - both his sports are in the same season (100m, 200m & 4x100 in track & baseball). Last year (freshman) it was a mishmash. The track coaches were terrific about him missing track practice and focusing on meets. The baseball coaches were very territorial, and definitely held it against him missing one practice a week to run track meets.
The track & baseball seasons both officially start next week, and he is nervous about doing track this year despite him running Varsity as a sophomore. He just doesn't want to get the baseball guys mad, but the baseball team has 24 kids on it (!) and everyone shares playing time - and it is just JV as they have no sophomores on Varsity - so how many AB's could he really miss when he'll only hit 3-4x a week anyways? You could be 2 for 2 with two bombs and you will come out after the 4th inning regardless.
As parents our take is that 2018 should do whatever he feels is best in making this decision. Personally I could care less about the impression it makes on the high school baseball coaches as in summer & fall he plays in a high level travel program that will take him to FL, AZ, etc. and get him infinitely more exposure than his HS program ever will. I do worry about him being good, not great, at both sports by not completely focusing in the spring - but he isn't going to the Olympics in either sport anyways, so have fun and compete.