I think an analogy you could use is that tennis players don't practice hitting into the net. baseball seems to be the only sport were coaches preach practicing something different than what you do in games (swing down, hit low line drives).
It can work for some. there are guys who hit 35 bombs despite saying they swing down or try to hit it low the other way. however there are also many prospects and even mlb hitters were the reports read "swing is lacking loft". there are cases of no power hitters hitting too many fly balls (Billy hamilton) but it doesn't happen often. way more often a strong hitter is not reaching his potential because he can't hit productive launch angles.
Recently quite a few average pro players turned into stars by raising their launch angle (Murphy, dozier,lamb) but many don't make that jump.
Maybe it would be good to learn that skill early, because few can learn that at 29 like Murphy. I'm not saying you need to learn that right away, for a 10 year old low liners are probably OK but no reason to not start that at 12 to 13.