Alrighty after a bit of debugging i found that under:
"SmartCrawl" (in the admin bar on the left)
--> "Title & Meta"
"NoIndex" is On
Troubleshooting done in realtime using search console's live URL tester to confirm first that smartcrawl being enabled/disabled was causing the problem.
Then after flicking "NoIndex" to off and trying again to import Yoast the problem does not arise again which is good. Still not 100% sure what caused it but was able to recreate it on two different websites (fresh-ish installs with no past SEO plugin data) after installing Smartcrawl and using the import options
I can confirm I have come across this problem on multiple sites running smartcrawl when using the yoast import feature after deleting yoast.
As in I think if you “import from yoast” but there is no yoast data to bring across it causes this problem.
It usually takes about a week to show up in google data console though.
Had this happen in January to a client which essentially removed their 100+ well-indexed pages with high impressions silently from google and spent a couple weeks trying to figure it out; only solution was switching back to yoast (reinstalling smartcrawl didn’t fix the issue)
I’ll recreate the error today on one of my websites and see if I can fix it by reinstalling smartcrawl cleanly. Is there any debugging I can do to help fix this possible bug?
Also while on topic of Defender are you guys working on blocking the "/?author=1" tag and other relevant defenses so that hackers can not easily find the username for the admin account and/or things like the admin login screen?
Can block it using .htaccess but this would be a valid feature for the less advanced users.
Have tried to re-create the problem with other websites and it appears to only be happening on this one website.
Had already tried your suggestions but that didnt fix it so will just work around it with CSS for now and re-install the theme later to wipe the issue.
Thankyou! I appreciate you taking the time to help.
Once again my issues have been magically resolved...
I swear i usually figure these problems out i think, all the problems i have had today were maybe server related or something because all is well now without changing anything. I will have to investigate and possibly change hosting if problems continue.
For now though; Thankyou Sajid!