If Google wanted to offer combined accounts going forward, that would be fine by me. Though I'd also prefer the option of disaggregated accounts, and of disabling specific services on accounts.

If they wanted to offer the option of merging existing accounts for which there was an underlying connection, that would also be fine. Though I'd really prefer they not do it with interstitials.

Merging identities in express violation of stated intent, or simply not offering the option to decline, is simply wrong, and will inevitably turn into a major PR disaster, as this is.