PGP keys typically use very higher security levels (like 4096 bits) compared to bitcoin ECDSA 256k1 and it is why people are more relaxed about sharing their public keys.
being bigger does not always translate into being safer. in case of PGP most of them use RSA keys and a 4096 bit RSA key offers nearly the same security than a 256 bit EC key (3072 RSA key has equal strength as 256 bit key used in ECDSA, and 7680 is the same as 384).
As of your safety argument: You are absolutely wrong.
i think you are confusing my reply! i never suggested address-reuse or never said it is "as safe" to reuse them. all i said was that you can't say it is unsafe today just because it can be broken some day.
all your arguments here can be said about hashes too. RIPEMD160 and SHA256 are going to become obsolete some day as they will be broken but you can't say it is unsafe to use them just because some day they will be broken. after all that is how cryptography has always been working for literary thousands of years