Verified on 4.2.0-0.nightly-2020-04-20-085107, after adding taint to node, node-ca pod number doesn't decrease.
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.