You are compromising the security of the people
Regarding the recent Ledger data breach, anyone that types a compromised email address knows that he/she has a ledger wallet and crypto. You are leaking to everybody the same information leaked by the hackers and you are compromising the security of that person by revealing the email, exposing him or her to phishing attempts and even to physical risk if the person that performs the search knows the identity of the owner. This is a very serious issue. Please consider sending the results only by email at least for these most serious data breaches where there is physical risk for the affected people.
There are many, many very good reasons why the service operates in this fashion: https://www.troyhunt.com/the-ethics-of-running-a-data-breach-search-service/