If the Comment feature is enabled, it is not possible to open the "Record Details" screen with the Comments or History section closed.

After opening the "Record Details" screen, you can close the Comments or History section by clicking the Comment or History icon.

Note that, if you disable the Comment feature, the Comments section does not appear on the "Record Details" screen, and you will be able to open records with the History section closed.
To disable the Comment feature, click the App Settings tab on the "App Settings" screen, click Misc Settings, and then uncheck the Enable comments check box. After that, click Update App, and then click Update App on the confirmation dialog.