I disagree, actually, although that depends on the sense.
If you do not have at least
some respect for the founding of a particular belief, then how can you have any respect for the belief? And if you don't have any respect for the belief, how can you have any respect for the believer, beyond mindless platitudes? And if you don't have any respect for the believer, why should you expect them to have any respect for your beliefs?
And this matters because it raises other questions; the motives of a secularist who has no respect for the religious should be questioned just as much as the motives of a political-christian with no respect for the non-religious. But if there is respect (in either case) then there is no real reason to worry.
Proportionality has nothing to do with it.
There is obviously a difference between not having a belief and not respecting the same belief. I've a lot of respect for, by way of example, Islam, but I'm certainly not a Muslim.