Google’s intention is to “call out” HTTP for what it is: “UNSAFE.”
The rationale is that on every website served over HTTP the data exchanged between the site’s server and the user is in the clear, meaning anyone with the ability to snoop on the connection, be it a hacker at a coffee shop or a repressive government, could steal passwords, private messages, or other sensitive information.
But HTTPS doesn’t just protect user data, it also ensures that the user is really connecting to the right site and not an imposter one. This is important because setting up a fake version of a website users normally trust is a favorite tactic of hackers and malicious actors. HTTPS also ensures that a malicious third party can’t hijack the connection and insert malware or censor information.