Agreed. It's your house, not his. We had a (functioning) window that we changed to a frosted glass block window several years ago. That time we didn't have to have a contractor tear down what he built against our wishes : ) During a remodel of my office, though . . . we were expanding the bathroom to make it ADA-compliant, and despite my instructions that it could not only be lengthened but needed to be framed out to allow an additional 1.5" in width . . . he just framed it straight out. Then removed and rebuilt it. NOW is indeed the time to make changes.

pkgallagher61his explanation to why he needs to close up the wall to ceiling doesn't make much sense to me. I think you should have someone else (a professional) to take a look at it just to get a second opinion. Is the picture of the window what he's planning on closing ? do you have another source of ventilation in the bathroom ?

Usually you can make a wall pop by using an accent tile. So you can tile other walls in lets say white tiles and then 1 wall to choose something with more designs on it or color that pops more.

We tiled above our window both before and after we changed out the window style. Are you using some weirdly extra heavy tile??

Extra vertical studs (screwed to top + bottom plates) + cement board (screwed to studs) = no problems. This "contractor" seems to lack basic building skills.

Hopefully I have the right idea of what you want, but that partition wall can easily be reframed for a glass panel insert. I do understand the contractor's reluctance to have just a stand-alone pony wall (no end post to the ceiling), the ability to properly anchor the end of the wall depends on the floor structure beneath the wall. There are, however, ways to do it.

However, simply opening up the wall itself for a glass panel? Pretty easy. You can open it up for a simple window as shown in the drawing below, or the upper header, cripples, and top plate can be omitted so the glass can go all the way to the ceiling.

They can reframe without having to tear down what is there. Add the new framing from the shower side, then go to the drywall side and run drywall screws to fasten the drywall to the new framing. Then cut out the opening. About 30 minutes of work and a couple of 2x4s to frame the top and bottom of the window opening.

FWIW, to make the shower a little more cozy, and to allow a bit more separation between the shower and bathroom finish surfaces, I would have considered headering off the shower entry opening as well. Along the lines of this:

Thank you, all. I talked to the contractor immediately and they tore down the wall. We will go glass instead. I now have a wing wall that is much smaller where the glass connects.