Really?
John 13:14 says " If I then, your Lord and Master, have washed your feet; ye also ought to wash one another's feet."
It is not the custom that priests only wash other priests feet, correct? So we know that the term "one another's feet" applies to the non-ordained.
Very few of the men whose feet have been washed at Mass in this ritual are being prepared for priestly service, correct?
So, since the ritual does not apply only to priests or candidates for the priesthood, what's the big deal?
I'm with you. I don't see it as a big deal either. But then I'm not bothered by pants wearing female lectors so what do I know?
I don't see how the expression "one another's feet" (the Greek simply says "υμεις οφειλετε αλληλων νιπτειν τους ποδας", i.e. "you owe others to wash the feet") can overcome this aspect of master vs. disciple.
Moreover, verse 16 speaks specifically of "apostle", further restricting those receiving this commandment to future priests.
Now, not every boy who gets his feet washed by a priest on Holy Thursday will become a priest, but the potential is there, because he is a boy. The potential is not there if he is a girl. This aspect is neglected if women's feet are washed.
I think this is an occasional departure and the expansion of the meaning to service in general, but when done to girls, or women, or even men of full age, the aspect of priestly preparation suffers -- and we sure could use more young priests.