You wouldn't want to use a browser so old it doesn't support ECDSA with P-256 (e.g. Android < 4.0). There would be a lot of scary stories in the media, but serv

You wouldn't want to use a browser so old it doesn't support ECDSA with P-256 (e.g. Android < 4.0). There would be a lot of scary stories in the media, but servers can switch to ECDSA (e.g. let's encrypt supports it). Devices which cannot be updated (e.g. credit card terminals) would need to be replaced.