In the old days, garage door openers used to be pretty simple mechanisms designed to help people open the largest, heaviest door in the their home so they wouldn't have to leave the comfort of their vehicle. But nowadays, there are plenty of reasons to consider updating to a more.. modern model.
Safety: Since the early nineties, garage door opener companies have been making products that follow a gold standard of safety- the new requirement makes sure that every machine has a reversing mechanism that detects object in the path of the door and makes it reverse if there is anything in the way. Basically, two sensors (about two feet off the floor) use infrared to detect obstructions and send a message to the openeing mechanism.
Noise: Newer models of openers are much more effective in reducing the awful noise garage door openers are famous for. Especially if you spring for a belt-drive opener, you can really cut down on the decibels you have to endure every day.
Security: Older models are subjected to what are called "code grabbers" because they have universal codes that can be easily cracked. New openers have rotating codes that update and change rapidly, making it next to impossible for someone to use a code grabber to get access to your door. Also, many new openers come with additional safety features.
There are many reasons to upgrade to a newer garage door opener, it's very much worth the investment.