Are there people here who would refuse to use a perl that was built without taint checking capability ?

There is at least one! Probably 80% of the Perl I write is either public-facing or at least untrusted-user-facing and therefore I use taint mode a lot and am extremely grateful for its demonstrable bacon-saving properties. Without it, perl would become much more dangerous with the upshot that it would either require some sort of front-end or wrapper which would peform the same task (tricky) or else $WORK would have to start looking at alternative languages. The latter would be a body blow as Perl is by far the best language in the toolbox.

I can see the attraction to TPTB given that they might not have much/any use for taint mode themselves but to excise such a fundamentally important part of the system just for a speed gain seems like throwing the baby out with the bathwater. And if you, dear reader, feel that it would be no great loss then take care because next time it might well be your favourite feature which is to be deleted. I can only hope that sense prevails.