It is necessary to retain your account, but an inactive account can result in the loss of privileges. Look for a service that estimates when the name will be available if you want to take advantage of promoted activity levels. Riot also provides explanations about how long accounts have before they are flagged as inactive if you search their site.

Starting January 22, your old account ID will no longer work. The creators of League of Legends, Teamfight Tactics, and Legends of Runeterra are creating a one-stop place for all player accounts.
Output: Starting on Jan 22nd, the creators of League Of Legends, TFT & LoR have created a single area where all players can access their accounts from under the same login so that you won’t need to find your original username or password combo to log in again

– If you are banned by Riot on one account, you can create a new one.
– You can use this opportunity to improve your behavior, but most people have more accounts banned later if they continue playing.