By definition a publc key can be made public without causing damage.
The point of using electrum is precisely to be able to sign transactions offline.
If one starts from the assumption that a private key has been leaked then yes the wallet is compromised.
Releasing the public key provides a very signfiicant security feature: the ability for the sender to verify the ownership of the destination address.
Sine the public key can be posted on many different key servers and social networks, the verifier can check all the sources and raise an alert in case it detects some insconsistency.
well no, that's why the whole change address thing is in BTC. If ECDSA is cracked and you have always used new addresses, then you coins are ok, and GAV and co can do an emergency patch, life continues, except fro those of you that had not used change addresses and possibly electrum/deterministic with and spent.