Hi, Wolfgang—
I copied all the fonts to a new document (file attached) and ran ConTeXt. The problem persists. The cause, I think, comes in the lines:
\definefallbackfamily[mainface] [mm] [STIX Two Text]
[range=digitsnormal,
force=yes,
features=f:oldstyle]
which used to give me oldstyle numerals.
bowen1@acbs-mbp ~ % mtxrun --script fonts --list --all stixtwotext
yields
identifier familyname fontname filename subfont instances
stixtwotext stixtwotext stixtwotext /Users/bowen1/Library/Fonts/STIX2Text-Regular.otf
stixtwotextnormal stixtwotext stixtwotextitalic STIXTwoText-Italic.otf
stixtwotextregular stixtwotext stixtwotextmedium STIXTwoText-Medium.otf