[mahmud]

omitting lexical scope, closures, pass by reference, and GC

None of those decisions were made for performance reasons, but because the creator of newLisp had no idea how to do them (lexical scope and call by reference were initially performance hacks, and actually make programs faster and/or smaller.)

A better name for the language would have been newBASIC, but even Basic is garbage collected. People who intend to use newLisp really need not suffer the parentheses. The language exists in familiar form as QBasic.

[prodigal_erik]

According to http://www.paulgraham.com/thist.html, at the time implementing lexical scope was a leap of faith. It was broadly assumed to be less efficient.