We have a perpetual Adoration chapel.
There are adorers who are signed up for an hour.
And there are adorers like me who drop in for short visits. Our Adoration Chapel is very busy and often there are a dozen or more people present for short visits.
It's really neat the way this works. We are going about our daily lives when out of the blue, we are "called" by the Holy Spirit to come away for a few minutes and visit Jesus the Lord. When this happens, I testify that I can literally hear the Holy Spirit "whisper" to my soul, and I've heard others say that they've heard the same kind of "whisper" to go to the Chapel for a visit.
We listen and say, "Yes" to the Holy Spirit and drive or walk over to the Chapel.
Interestingly, the Holy Spirit doesn't tell us to go home first, change out of our casual clothing or work clothing, and dress up.
It seems to me that we should allow the Holy Spirit to tell others how to dress when they are in the Presence of the Lord Jesus.
If the Holy Spirit has told someone to come to adore Jesus, but didn't tell them to dress up, then we have no business telling them, either out loud or in our minds, to "Go dress up first."
We need to give this issue to the Holy Spirit and ask HIM to convict His disciples about their dress habits.
And IMO, we need to trust the priest of the parish offering Adoration. If there is a need for a dress code, the priest will post this information at the entrance to the Adoration chapel or area. If the priest does not post any dress code, then we need to trust that the priest is competent and is responding to the leading of the Holy Spirit in his own life.
I agree with others who say that often, people come to Adoration in great distress, desperate for the healing Presence of the Lord Jesus. A few summers ago in our city, a little boy was drowned. I happened to be in the chapel when his distraught family, dozens of them, arrived in the chapel. They were definitely not dressed up, and they were definitely not quiet. It was probably the most meaningful time that I have ever spent in the Chapel. I was able to watch Jesus comfort these dear people who had suffered an awful tragedy.
Also keep in mind that many times, sinners come to Jesus, and these people will not always be dressed in modest clothing. This happened in the Bible, and it's still happening today. Again, we must TRUST that in His Own time, the Holy Spirit will talk to His disciples about their dress and modesty issues. But His time is not necessarily our time.