I think the difference in thinking here is you want everyone to " recognize the improvements" while many others don't feel we have enough data to make that assessment of real improvements vs a hot streak to start a season.
Let's look at one of the guys you discussed:
Rio Ruiz has some encouraging numbers between last year and this year.
Stat 2019 2020 Dif
xBA .233 .221 -.012
XSLG .362 .443 .081
xWOBA .297 .319 .022
Barrel% 2.8% 17.4% 14.6% 92nd percentile in MLB
exitvel 88.4 91.7 3.3 MPH 85th percentile in MLB
LA 11.3 15.6 4.3
K% 21.3% 28.2% 6.9% worse
BB% 9.7% 12.8% 3.1%
So it seems like Ruiz is hitting the ball with more authority, getting more launch angle, which is course has hurt his strikeout rate and expected batting average a bit. Right now his barrel and exit velocity is among the top in MLB. Pitchers are starting throw him a bit more offspeed this year to adjust so we will have to see how this goes as the season progresses.
The improvement in exit velocity and barrels is impressive so he's actually one that I'm interested to follow and see if it levels out or if this is some kind of sustained improvement as he enters his peak years.