One thing that is important is that he is talking about "a computationally complete end user programming language". I think they key in that phrase is complete. Quite frequently language designers focus on minimality (my own bias towards Lisp and towers of macros is in this vein). Two of the three paradigms in Thomas' (and Meijer's) article are relational database and XML, which aren't really treated as basic types in most language designs. This usually means that they get pushed out to libraries.

Languages need a way to assimilate these paradigms in a way that makes them look seamless. XDuce is cited in Thomas' paper. If you look at the XDuce examples, you'll see that the syntax for dealing with XML looks like the syntax for dicts in Python. This is certainly more straightforward than most languages that I've seen, although not quite as nice as E4X. There are lots of examples of Python libraries for XML that look like XDuce, but none that look like E4X. If you wanted to support E4X style syntax for XML, and an analogous syntax for SQL queries and tables, you'd have to hack Python.

What to do?