Invalid date field, BibLaTeX produces no output

Question

This is an MWE to reproduce the same effect, as I encountered on a larger BibLaTeX database.

The database was created in beginning of 2019 and used since then on a regular basis (twice a year). I can't remember having problems like that.

As you can see, the date entries are as described in the BibLaTeX manual, section 2.3.8, in YYYY-MM-DD, enclosed in either curly braces or quotes, followed by the comma.

Here is the MWE including the BibLaTeX file with two entries:

\documentclass[10pt]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[ngerman]{babel}
\usepackage{csquotes}
\usepackage[backend=biber,style=numeric]{biblatex}
\newcommand{\TeXLive}{\TeX{}Live}
\begin{filecontents}{\jobname-2.bib}
@Manual{texlive-de-2020,
  editor =   {Berry, Karl},
  title =    {Anleitung zur \TeXLive-Installation},
  date =     {2020-03-28},
  subtitle =     {Version 2020},
  langid =       {ngerman},
  translator =   {Dr. Ziegenhagen, Uwe},
  pagetotal =    96,
  langid =   {ngerman},
  keywords =     {manual},
  note =     {Bestandteil der Online-Dokumentation von \TeXLive,
                  Datei \texttt{texlive-de.pdf}}
}
@article{worland_renewable_2015,
  title =    {The {Renewable} {Energy} {Source} {That}'s {About}
                  to {Boom} {Again}},
  issn =     {0040-781X},
  url =      {http://time.com/3978215/hydropower-us-growth/},
  abstract =     {'Whether we like it or not, over the next 20 years
                  roughly the world will double its hydropower
                  capacity'},
  urldate =  "2016-12-07",
  journal =  {Time},
  author =   {Worland, Justin},
  month =    jul,
  year =     2015,
  keywords =     {energy outlook, energy production in the u.s.,
                  Hydropower, u.s. energy, u.s. energy production},
}
\end{filecontents}
\addbibresource{\jobname-2.bib}
\begin{document}
% \cite{texlive-de-2020}
\nocite{*}
\printbibliography{}
\end{document}

After running latex I call biber and get this messages

Running `Biber' on `test' with ``biber test''
INFO - This is Biber 2.15
INFO - Logfile is 'test.blg'
INFO - Reading 'test.bcf'
INFO - Using all citekeys in bib section 0
INFO - Processing section 0
INFO - Looking for bibtex format file 'test-2.bib' for section 0
INFO - LaTeX decoding ...
INFO - Found BibTeX data source 'test-2.bib'
WARN - Entry 'texlive-de-2020' (test-2.bib): Invalid format '2020-03-28' of date field 'date' - ignoring
WARN - Entry 'worland_renewable_2015' (test-2.bib): Invalid format '2016-12-07' of date field 'urldate' - ignoring

The next latex run will complain about the empty bibliography file

LaTeX Warning: Empty bibliography on input line 49.

I can't see any error in my BibLaTeX files. I think they are fine. What is going wrong?

Clear the Biber cache as described in https://tex.stackexchange.com/q/140814/35864. This cache is stored in a temp directory and might get corrupted (recently many users of Mac OS have reported issues, maybe that OS tries to clean up the temp file and damages the cache). See also https://tex.stackexchange.com/q/541486/35864 and https://tex.stackexchange.com/q/543837/35864 as well as the questions linked there. — moewe, May 08 '21 at 12:31
@moewe I suggest marking this question as duplicate or answering my question, I would gladly marked it as solved :-) — Jan, May 08 '21 at 15:22
Closed as a duplicate to avoid ... well ... answer duplication in too many places. Just for the data point: On which OS was this? — moewe, May 08 '21 at 21:12

Invalid date field, BibLaTeX produces no output

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