I would certainly never advocate for a person to wear a certain colour today because it would mean nothing as the commandment was given to the children of Israel under the old covenant. It is of historical interest that the Israelites were to have the blue ribband sewn in to their clothes throughout their generations to remind them of their obligations.
Although the Roman Catholic Cult is a cult that came about in the time of the new covenant and so, like us,they do not come under the ordinances of the old covenant ruling regarding the blue ribband, I just found it interesting that the blue is totally missing even though the purple and the scarlet and the gold is present. As children of the new covenant we still look back at the blue ribband of the old covenant as a reminder that we have the obligations to live correctly under the new covenant as children of Christ. We have been invited to the wedding feast of the lamb but woe to the person who turns up without wedding clothes on.
Matthew 22 Authorized (King James) Version (AKJV)
2 The kingdom of heaven is like unto a certain king, which made a marriage for his son, 3 and sent forth his servants to call them that were bidden to the wedding: and they would not come. 4 Again, he sent forth other servants, saying, Tell them which are bidden, Behold, I have prepared my dinner: my oxen and my fatlings are killed, and all things are ready: come unto the marriage. 5 But they made light of it, and went their ways, one to his farm, another to his merchandise: 6 and the remnant took his servants, and entreated them spitefully, and slew them. 7 But when the king heard thereof, he was wroth: and he sent forth his armies, and destroyed those murderers, and burned up their city. 8 Then saith he to his servants, The wedding is ready, but they which were bidden were not worthy. 9 Go ye therefore into the highways, and as many as ye shall find, bid to the marriage. 10 So those servants went out into the highways, and gathered together all as many as they found, both bad and good: and the wedding was furnished with guests. 11 And when the king came in to see the guests, he saw there a man which had not on a wedding garment: 12 and he saith unto him, Friend, how camest thou in hither not having a wedding garment? And he was speechless. 13 Then said the king to the servants, Bind him hand and foot, and take him away, and cast him into outer darkness; there shall be weeping and gnashing of teeth. 14 For many are called, but few are chosen.
The Roman Catholic Cult are just a part of those who don't take heed to the teaching of the Bible and will be cast into outer darkness; where there shall be weeping and gnashing of teeth, but we do see from the scripture that that cult is a major player in the events that unfold in the last days.
As true Christians we effectively wear the blue ribband in our hearts and minds and read and study the scriptures daily to make sure we are living as the true children of the promise and that we are dressed suitably for the wedding.