Termarr Johnson no doubt has a compact frame. Most listings I see have him at 5'7", but I've seen him listed as tall as 5'10".
Most listings for Termarr I have seen list him at 5'7". That is well below average for a major league baseball player and would likely put him in the top 10 for shortest active players in MLB today.
Statcast doesn't publish data on a players bat speed or swing length for minor league players. Termarr is known for having a compact, quick swing with excellent bat speed. If this is true, then he might have a competitive advantage the Bucs may utilize by the time he gets to AAA or maybe in AA.
The Pirates are changing their hitting philosophy which is described in an earlier article on this site, Matt Hague Telling Stories . If you have not read it yet, I highly recommend it. Hopefully this change in philosophy about focusing on reducing strikeouts, higher OBP, and quality contact will better utilize Termarr's physique.
If Johnson really does have excellent bat speed (not as fast as Oneil Cruz), but let's say he is in the top 100 of active MLB players in terms of bat speed which in my eyes would qualify as excellent. That would put him at roughly a 73.8 MPH swing and around the 85th percentile.
There isn't really anyone who at 5'7" and shorter comes close to that. The closest one is Eguy Rosario from the Padres who is the same height and has been getting brief stints in the MLB the last few years. He has been seeing more success in the majors and minors the last couple of years. His average bat speed 72.5 MPH which puts him around the 69th percentile. Note that this is out of 650 eligible hitters with any number of pitches seen.
It seems like the Pirates have some unicorns in their organization like Paul Skenes who won Rookie of the Year and was a Cy Young finalist and had the lowest ERA for a rookie with at least 20 starts since 1920 and had the lowest ERA of any pitcher this year with at least 130 innings pitched. Another Unicorn is Oneil Cruz who has the highest average bat speed for a left-handed hitter in MLB. Ke'Bryan Hayes was on pace to possibly break records for his career combination in defensive runs saved, outs above average, and defensive WAR before he got hurt. Hopefully he heals himself back to normal. When there are these many players who are the best in the league at important parts of the game the team must win, and cannot waste the oppportunity.
I'll post more detail on the unicorns in the Pirates organization in later articles.