odbc automatically locates db drivers in most cases, but it fails to automatically locate SQL Server drivers installed with homebrew on macOS running on Apple Silicon. Examples [1], [2].
A way around this is to set ODBCSYSINI in .Renviron:
ODBCSYSINI=/opt/homebrew/etc
Without the environment variable set, odbc doesn't locate installed drivers:
odbc::odbcListDrivers()
# [1] name attribute value
# <0 rows> (or 0-length row.names)