As a millennial I can totally relate to this. Actually, brick-and-mortar shopping sometimes gives me anxiety because I find it overwhelming now -- rifling through tags for price, fabric content, country of origin, etc, it feels tedious and I always worry someone will think I'm trying to shoplift when I handle garments, especially accessories (yes, this is ridiculous and probably generational).
I dislike the lighting in most retail spaces, and there seems to be a continuing trend to crowd as much product onto the floor as possible, so there's more and more racks, less open space. I'm not an unusually claustrophobic person, but I find a lot of shops' merchandising lately to be crowded and chaotic (this might be a regional issue -- I don't live in a high-end retail environment).
When I see something I like in person, my first thought is always, "where can I find that for cheaper online?" The internet has made e extremely skeptical of MSRP.
I do sometimes make trips to try things on in person that I've seen online (I love being able to check online to see what's in stock locally). But I honestly can't remember the last time I purchased a garment for myself from a B&M shop.