These are the packages that would be merged, in order:

Calculating dependencies ...

!!! Problem resolving dependencies for =dev-php/pecl-mongodb-1.16.2-r1
 done!
Dependency resolution took 0.83 s (backtrack: 0/20).


!!! The ebuild selected to satisfy "=dev-php/pecl-mongodb-1.16.2-r1" has unmet requirements.
- dev-php/pecl-mongodb-1.16.2-r1::gentoo USE="-sasl -test" PHP_TARGETS="-php8-2"

  The following REQUIRED_USE flag constraints are unsatisfied:
    php_targets_php8-2

  The above constraints are a subset of the following complete expression:
    any-of ( php_targets_php8-2 )