Is there a way to hide <l internal calls>? I think its unnecessary repeated annoying remainder taking space.

Hi. This message means some lines were folded by a console, it is possible to hide them by turning off the console folding, but it would make console output ambiguous. https://www.jetbrains.com/help/idea/settings-console-folding.html

"ambiguous" or not, its a user to decide. If users don't want to see it then let them, don't enforce it.

Please follow the related request on YouTrack: https://youtrack.jetbrains.com/issue/IDEA-188173

Just right click that line and click "fold line like this".
One console will open ,there you just remove that line from that console and click ok