There are multiple parts involved when using Recaptcha.
One part is the javascript code in the frontend to analyse the behaviour of the user. (This part is included with recaptchav2_render.)
The second part is the hook recaptchav2 that is executed on the server ONLY when the form is sent (to check the g-recaptcha-response-value submitted with the form).
When you only remove the hook, then the javascript code (on the frontend) is still working (and you see the tick box), but you never verify the submitted value.
Have you ever tried to analyse the response value of the API-call to Google, like I suggested in your last thread regarding Recaptchav2:
For example if your secret key is wrong, you should see something like this in the error log
[errorCodes:ReCaptcha\Response:private] => Array
(
[0] => invalid-input-secret
)