Cricket umpiring

To stand/change position for two hours at a stretch is a tough call in itself, particularly in trying weather conditions; but to be loaded with making 'unchallengeable' decisions in the face of advanced technology use renders the task almost impossible of achievement. There's no chance now that electronic monitoring and display will be withdrawn from the sport of cricket (or any other sport). While some enthusiasts would claim that (on-field) umpires still hold sway, their role has forever changed, and will continue to do so, by accepted use of radar, lasers, etc. as "aids" in decision-making. Many would argue that including 'hawkeye' and allied electronic wizardry in the game has added to the entertainment value. It's not easy to counter this viewpoint. Nonetheless, umpires are at times made to look second-rate via a decision that clashes with the electronic result. How much can the human frame withstand? Across the board, can the eyesight and powers of judgement of an umpire remain acute enough for 2 hours/6 hours versus the unfailing (?) operation of non-human checking equipment? Will the day arrive where field umpires will be ball-counters and all else will go to the Third Umpire for result? Wow!