This is a key point - airport-style security at train stations would be a disaster. Stricter employee screening and more dog-handler teams, on the other hand, is a reasonable proposition. I think it's difficult though to trust the TSA to do this well and to trust it not to escalate into something much more intrusive.

Also notable though, is that it seems that much of this is about increasing TSA intelligence / data analysis:

The new bill “addresses gaps in TSA’s approach to assessing security risks and will help the agency better fulfill its role as a hub of analysis, planning, and information...”