An interesting perspective...
I think in a historical context, everybody wearing the identical same clothing had several advantages. Whether a doctor, an administrator, or a farmer, a sewer worker these uniforms, the identical clothing creates a beginning if very shallow, artificial equality.
Make everybody the same and you are equals, brothers, sisters of whatever the training. Dressed differently and the commonality between us is not enforced. Uniforms also allow far greater destruction of clothing. The stuff I normally wear would be stretched, pulled, shredded if it were my standard gear for training sessions. Don;t know about you, but I enjoy wearing clothes I've paid for, as opposed to destroying them anyway?
The belts or sashes can be a very useful tool for training exercises and drills. It can be a practical tool unto itself. To my point earlier, belts remind us though we are like everyone else in the room, that we are the "exact" same, the belt colors are a visible acknowledgement in parallel that we are different at the same time as well. I accept the different belt colors myself as a visual palette for the lessons available to a teacher that class. Rotate teachers, have different classes in multiple locations where I might not know you specifically, the colors are a hint at the fundamental skills available from which to build the lesson... IMHO.
All that being said, I agree entirely with a uniform, that clothing provides an attacker certain advantages solely because of the fiber, strength of the fabric itself. If I do not wear it you cannot choke, jerk, pull, hold me with that jacket in particular.
Like Chen Zen said, we need to practice in regular clothing too, see what that does to our techniques, our mobility among other things. Some daily wear can be highly useful tools as well! But in terms of grappling, the classic judo dogi, the standardized uniform jacket does provide a technical disadvantage provided they can grab us without getting ~destroyed~ on the way in. I would call a tangible disadvantage but minor one.
Merely my opinion, I could surely be mistaken,
I have to respectfully disagree. I often wear rash guards so no tearing, problem solved. And even when I wear t shirts I've only a couple times had them tear. As for the equality/commonality/brotherhood thing I find training hard together day in and day out, helping each other prepare for competitions, etc. takes care of that. I get more of a brotherhood feeling from my mma team with no uniform than I ever did in TKD or Kenpo just because the nature of it is tougher and we really suffer together through it, help each other get ready to compete and that sort of thing. If you need uniforms to get people to treat each other as equals those people don't belong in the gym and need to grow up first. There's plenty in common when getting put through the same grinder together. For me especially, I've had enough of uniforms from the military, it's just stifling in my opinion. It really doesn't make much difference unless it's a part of 24/7 daily life anyway. Formalities have always come across as distracting for me. As for belts, they are great for credibility and sometimes telling new schools where you stand but there are so many different belt systems even within the same styles that that is limited in usefulness. Also you have to watch out for people getting arrogant because of their belts I've seen that too. I'm certainly not against them they can be very positive, but certainly not crucial. I know what I can do with or without a belt and my performance on the mat will tell a new coach/instructor where my skills lay. A couple minutes of rolling or sparring says far more than any belt.
Please note, I'm not saying uniforms will necessarily be negative or you shouldn't use them, if you like that than great, I just know from experience that they aren't required for the things you mentioned. The attitude of the students and instructor/coach as well as the kind of training is what brings about those things.