The fix for SERVER-109934 led to some mongos parameters being unconditionally set in some Evergreen variants, e.g.

        --mongosSetParameters="{maxRoundsWithoutProgressParameter: 20}"

While this is fine for master, there were issues with previous versions, in which the parameter was declared as "test_only" (v8.2) or did not even exist (v8.0).
This made several test variants fail in their multiversion test setups.

A potential fix is to exclude these parameters from being set when starting up mongos executables that are before v8.2.0.
While this is a hack, several such workarounds have been added over time, so it seems like it is a reasonable approach.