I doubt it. There isn't really a justification for his salary at the moment unless I am missing all the work he does outside MotD (which I may well be).
The issue is that they couldn't replace him with someone else and then pay them less. They would either replace him with Jenas or a female lead, both of which would cause an absolute storm if they were paid less than Lineker.
Sitting in the job doesn't mean you're worth as much.
If he's got his fee in a talent based position from negotiating with what he can be offered elsewhere it doesn't then mean that the next bum on the seat is worth the same amount as needed to keep Lineker.