Quantum computing will have the ability to break most existing encryption methods. People and, in particular, governments are collecting encrypted messages/files/etc. for decryption in the future.
These saved “messages” will include traffic to websites. This will include commerce (think gun and ammo purchases), blogs (this one is not encrypted), forums, etc.
A reliable source recently told me to expect RSA encryption to be broken in three years and government entities are preparing for that.