Look at the issue as "micro vs. macro".
I realize that FOR ONE SCHOOL it could seem like a 1-for-1 rule could give them too many transfers. But in a macro sense, every scholarship kid who transfers just goes to another school, so across the whole "scholarship ecosystem" there is harmony.
Also, if Alabama wants to take transfers to replace "five kids who went to the NFL early", they have to use their regular 25 ICs. A 1-for-1 transfer rule should be in place simply to keep ANY school from being devastated by transfers, such that they can never get back to 85 under the 25 per year limitation.
And, yes, I agree with you that any 1-for-1 IC "exemptions" could only be used for transfers-in. Losing 7 transfers doesn't allow a school to sign 32 high school kids.