most bcftools commands have the -e and -i options to select some variants. bcftools view have more options for filtering "-m, -M , --types , etc..` . The main goal of bcftools annotate is to remove/add information from a VCF input.

bcftools annotate -x FILTER/PASS file.vcf.gz

you're NOT filtrering out any variant here, you're just removing the information FILTER/PASS from the variant

bcftools view -f PASS file.vcf.gz

here you DO filter out variants that don't have the FILTER=PASS