That’s not the issue, though. The issue is that Gmail are too zealous in blocking and wind up blocking legitimate email with no way for the sender to debug what

That’s not the issue, though. The issue is that Gmail are too zealous in blocking and wind up blocking legitimate email with no way for the sender to debug what happened. From your perspective, nothing happened because how do you prove you never got an email you never knew was sent to you? The people having problems here are non-Gmail senders sending email to Gmail recipients.