Google and a lot of other organizations aim to kill unencrypted HTTP. Site data collection/selling aren't primary motivators for implementing it. It's the HTTPS Everywhere/HTTPS Always On movement. The problem that most of the people implementing SSL to get a small SEO boost is that they aren't running secure and optimized SSL setups. People think installing a cert is all that's necessary. That can't be further from the truth.
They don't implement:
- HTTP/2 + APLN
- Modern, optimized cipher suites
- Forced server side cipher suite order
- Daily rotated EDH (Ephemeral Diffie-Hellman)/Session Tickets
- HPKP (HTTP Public Key Pinning)
- Disabling of SSLv2 & SSLv3
- SSL Cache
- OCSP (Online Certificate Status Protocol)
- HSTS (HTTP Strict Transport Security)
- Secure Cookies (Cookies over SSL only)
- No compression
Besides, as more sites switch to HTTPS, you're going to need it if you want to glean any referrer info from a site running HTTPS. You get nothing if your site is HTTP and the referrer is HTTPS.
HTTPS to HTTP - the poor man's referrer blanker.
Most importantly, don't forget the canonical meta tag when you switch.
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