Therefore, it would be considered a part of worship. But to say that inviting people is the actual thing and worship is nothing is not correct and statements like this are based on ignorance. Usually the elders of this movement don’t even say something like this. We don’t know where you heard this from but even inviting people is for the sake of worship. So, how could worship be inferior to invitation when the invitation is done for the worship? In order to pray, a person must make wudu, which is necessary for the prayer. Just because it is necessary for the prayer it doesn’t mean that it is better than the prayer or bigger than the prayer in degree and kind. The prayer is more important than the wudu but it won’t be accepted without it.
The main thing to do is to worship Allah and inviting people towards this is also an obligation of all the Muslims. The movement itself has many benefits, it is easy to join, it is geared towards training people anybody and everybody etc. therefore, people should try to join this movement. But we have not heard from any scholar that it is incumbent to go out in this movement. The basic principle is that when bad and evil become so common in people, Muslims should try to get rid of them as much as possible so much so that there should be no evil and bad. For this task, if just a few people are needed then it would be obligated for those few people to stand up but if it requires everybody to stand up then it becomes incumbent for everyone to stand up.
Nowadays it looks like even if everybody stands up the conditions will not become better, it just looks like that way. Therefore, everybody should stand up for this responsibility and fulfill the duty of enjoining good and forbidding evil.