Yes, it can be done through the GUI as well - either in each page level or global level from admin center.
Disable the comments footer from admin center (global setting) :
- Navigate to Admin Centers by going to App Launcher > Admin
- Under Admin Centers, choose SharePoint
- Once in SharePoint Admin Center, click on Settings
- Scroll all the way down to the bottom of the Settings screen to Comments on Site Pages section. By default, comments are enabled on all pages. If you wish to disable, just choose appropriate radio button and click OK
Go to this URL:
And please do below-highlighted settings:
And I think for the social collaboration setting, you can check the "Enterprise Social Collaboration" setting from the same global setting page.
This global setting option usually takes 10-20 minutes to take effect
on all sites/pages in your tenant
Once disabled globally, comments cannot be enabled back by Site
Owners or Site Members
Just like with previous option, disabling comments globally does not
remove the comments history. Once globally enabled, the whole
Comments thread will be back!
Disable the comments footer from site page level :
- Edit the page by clicking the Editbutton
- At the bottom of the page in the Comments section, toggle the switch from On position…
Please refer the below article for the details:
2 ways to disable modern page comments