Why the feeds are unencrypted is irrelevant, as are all the statements about how easy or hard it should have been to "do it right."
The only relevant issue is "what effect does the compromise have on the usefulness of the intelligence gathered by the UAV?" For a variety of reasons I would say this causes only a very small amount of degradation in the usefulness or lifespan of the intelligence. Do I think it should be fixed? Yeah. Do I think it's the most life-saving use of engineering resources? No. Do I think all the arm-waving is going to cost more than the solution? Definitely.
The only relevant issue is "what effect does the compromise have on the usefulness of the intelligence gathered by the UAV?" For a variety of reasons I would say this causes only a very small amount of degradation in the usefulness or lifespan of the intelligence. Do I think it should be fixed? Yeah. Do I think it's the most life-saving use of engineering resources? No. Do I think all the arm-waving is going to cost more than the solution? Definitely.