I checked my competitors, and they were experiencing the same thing. All i-gaming pages in Indonesia disappeared from brand keyword rankings, even the biggest ones.
Recently, I have been using the method: aged domain then inserting the landing page into a sub directory using an e-commerce template then using alternates to the subdomain or to pages.dev and others. but it no longer works, a day ago all the pages were 90% gone
'aged domain' is a no-go tactic. it only works when the domain has a very solid track record matching your current content, otherwise, waste of time and money.