Earlier quoted context omitted.
The reality is that just about every single lisper will insist how they don't see the parenthesis and they are not a problem, and just about every single lisp has some ugly ad hoc hacks to reduce their clutter. They just differ somewhat between lisps. Scheme (and descendants like racket) went so far as to make [] and () interchangeable. So you will in fact see brackets in some scheme most e.g. (let ([a 1] [b 2]) ...)…
Only R6RS made () and [] interchangeable. That was hugely controversial, with opponents (myself included) thinking it was a waste of 1/3 of the matching pair symbols. And the suggested use was not quite the syntax you showed: http://www.r6rs.org/final/html/r6rs-app/r6rs-app-Z-H-5.html
Interlisp also for example uses square brackets. The left square bracket is equivalent to a round bracket and the right square bracket closes all open levels of brackets.