It's never been a problem for me, I've killed almost every bounty and gotten the achievements for them quite easily, because there are always tons of bounty squads going. You just need to use the LFG menu to find them for the zone you're looking for. If you seek to grab a bounty by yourself, and then call people to it, then yeah it will probably be more difficult to get it done because everybody is doing bounty rotation squads. It's not ideal, and after a few months they may need to make them easier, or change up rewards or something to keep enticing people to them, who knows, but as of right now they're pretty easy to get done if you look.