I think not as much as you would think for younger players, the big deal is for players who have (or will that year) graduated, but have a year or two of eligibility left.
Unless I am wrong (and that happens a lot) this is how it works for say a Freshman:
Has 5 years to play 4. Time starts when they enroll. So:
a. Year 1, plays 5 or more games, is unhappy, decides to transfer. Year one was not a “red shirt year”, so “Freshman year” has been burned. Has to sit out year 2, which is a “red shirt” year. Has years 3, 4 and 5 to play at new school.
b. Year 1, plays 4 games or less, is unhappy, decides to transfer (decision could be announced in September after the season, no difference). Year one is considered a “red shirt” year. Has to sit out year 2, which is not a red shirt year, is his “Freshman” year, but still can’t play. Has years 3, 4 and 5 to play at new school.
No difference between a and b.
Obviously where there is a big difference is if the kid does not have to sit out. Could happen for various reasons, but the one we see the most often is he has graduated. So, there he is playing his say 4th year and doesn’t like his playing time, he can pull a Clemson QB and stop playing before getting to 5 games and transfer. That does count as his “red shirt” year, not a year of playing, and since he doesn’t have to sit out to transfer, does him a lot of good.
There are other reasons a kid can transfer without sitting out that could let a younger player take advantage of the rule. The rule that lets you transfer closer to home due to a family emergency. (The running back that went to USC then transferred to UofA, can’t think of his name.) Under the old rule, if he had played in 1 game at USC, while he didn’t have to sit out, he would be a Sophomore at UofA the next year. Under the new rule, if he had played in 4 games or less, could play the next year at UofA as a “Freshman.” He would have used his “red shirt” year at USC and would only have 4 years to play 4 at UofA.
I could be wrong on this. Let me know if I am.