Welcome to our forum, @Karel_Brinda! While it’s not possible to automatically modify citation/bibliography links (only removing them), the citation style can be modified with CSL’s web editor to include the actual DOI links in the bibliographic reference. The Paperpile links will still be active unless purposefully stripped, but the DOI links should be clickable.
Would that be a suitable solution, or would it clutter the reference list too much? I updated the style just in case; you can download it from minimal-style-for-grant-proposals-DOI.csl (3.6 KB).