It wont be too bad. If you mean computers used commercially, Unix keeps a running total of seconds since the epoch and DST only affects whats displayed as time. Nothing will fundamentally change for these systems. In windows server products it wont be a problem, and some windows clients use an automatic patch process. Air gapped computers may have some hacky process around DST, but its a pretty solved problem.
It wont be too bad. If you mean computers used commercially, Unix keeps a running total of seconds since the epoch and DST only affects whats displayed as time. Nothing will fundamentally change for these systems. In windows server products it wont be a problem, and some windows clients use an automatic patch process. Air gapped computers may have some hacky process around DST, but its a pretty solved problem.