Q: Is disavowing links enough? Some link removal and link deletion tool claim that it is required to remove links.
No. Link removal is not required to get a Google penalty lifted.
As Google officially stated here , links that you cannot get rid of should simply be disavowed. This is the case for many Web 2.0-Links, Article Directory Spam, Link Directory Spam and of course Blog Comments.
Of course Google wants to see effort and there are some very simple ways to show them all your effort.
There are great ways to achieve high success rate with removal and reconsideration. Become an LRT Certified Professional and you will learn those ways.