In a hundred years we'll be replacing our organic lungs with plastic ones that we can hot-swap.
According to this, there's some level of lung rejection in 90% of patients.
https://utswmed.org/medblog/lung-transplant-rejection/
That's a lot of management for a critical system... even if it's treatable.
Howevee, with current advances in mRNA treatments, CRISPR gene therapy, lab grown organs, and general medical, scientific, and computational advances, it seems inevitable that the outcome of transplants will increase greatly. I wouldn't be suprised if we see rejection become the rare outcome within my lifetime.