I suggest adding a tab to the top of the Top Blocked Domains on the dashboard so that in addition to seeing all of the top domains ever, you could see the top domains of the last X period such as 24 hours or 7 days. This could assist with locating new issues within the network.
For example you add a new blocklist and everything seems fine then the next morning you check your pihole and see in the last few hours a big spike in blocked requests for api.device.tld that is being blocked for privacy reasons but now you smart toaster or something has stopped working.
The Long-Term Data page allows access to Top Blocked Domains, Top Domains and Top Clients using any time range you like (you can even use the Custom Range selector).
I think this is a misunderstanding: the "top lists" at the dashboard show the top items within the last 24 hours. They don't show the top items ever. You can verify this by clicking on the links of the domains and see when they were requested.