I was a graduate professor at an R1 university teaching IT field where students went directly to Amazon, Uber, Microsoft, Meta, etc. Graduate school class sizes are small (~20 students) and in a normal class I had MAYBE 5 US citizens. The rest were primarily Chinese and Indian who needed an H1B to work.

If a large tech company needs a resource, H1B resources are the majority of what is available and large corps don't care about an extra $100k/yr.

Smaller firms will, however, and they will need to start switching their thinking as they cannot afford an additional $100k (effectively doubling what that resource costs). So overall there will be less opportunities for Int'l students if this passes and still doesn't solve the issue of so few US citizens going to grad school.