I've tried to implement a journal-like footnote with the authors'
affiliation for each section/chapter, by adapting things from the wiki here
<https://wiki.contextgarden.net/Table_of_Contents#Author_in_ToC> and here
<https://wiki.contextgarden.net/LaTeX_Thanks>. However, one thing that bugs
me is that any note name I choose other than "thanks" does not work, and I
have no clue why. Am I missing something, or is there a more elegant way to
implement this?

As an aside, I'd rather have the footnotes below the "thanks" notes. Is
there any option that does this?

\setuplist[section][
 textcommand=\SectionTocEntry,
 after=\blank,
]
    \define[1]\SectionTocEntry{%
 \doifnot{\rawstructurelistuservariable{author}}{}
{\start \it  \structurelistuservariable{author}\stop\space-- \crlf}%
 #1% title
 \doifnot{\rawstructurelistuservariable{subtitle}}{}
{\crlf\structurelistuservariable{subtitle}}}
    \setuphead[section][
 after=\setup{section},
 align=center,
 number=no,
 style=\bold
]
    \startsetups section
 \blank
 \midaligned{\it \structureuservariable{author}}
 \blank\stopsetups
    %\foonote{\structureuservariable{affiliation}}
    \definenote[thanks]%[numberconversion=set
2]\setupnote[thanks][rule=off]\setupnotation[thanks][numberconversion=set
2] % or set 1
    %\setupnote[footnote][location=bottom] % does not work
    %% all notes, footnotes etc.\setupnotation[
 alternative={left,bottom},
 hang=fit, % if commented, hanging is larger
 indenting={yes,small},indentnext=yes, % please, indent everything,
should be default
]
    \setupinteraction[state=start,color=black,contrastcolor=black]
    \setuphead[subject][align=flushleft,style=\bfb]
    \starttext
    \subject{Grande lista de autores}
    \placecontent[alternative=c]
      \startsection[title={Whatever}][author={A. Uthor},subtitle={I’d
like to say}]
This is a section.\stopsection
    \startsection[title={Segunda seção}][author={Fulano de
Tal},subtitle={Uma segunda seção de teste}]
This is a section.\stopsection
    \startsection[title={Terceira seção}][author={Alberto de
Paiva\thanks{asdf}},subtitle={Uma terceira seção de teste}]
This is a section.\stopsection
    \startsection[title={Três autores}][author={Sicrano de
Tal\thanks{Universidade de Tangerinas} e Alberto
Steinenberg\thanks{Universidade de Nilfgaard}},
subtitle={Uma seção de teste com dois autores e comentário}]
This is a section.\footnote{Só de teste.}\stopsection
\stoptext