Safety of Older Electronics

Some electronics never die. They just get moved to secondary, tertiary, etc. systems. In my case, I have two old receivers connected to televisions. I'm guessing one is 25 and the other 30 years old. The remote sensors are on all the time and occasionally one forgets to turn the receivers off. They can be replaced with relatively inexpensive amplifiers for how they're used, but I thought if it ain't broke don't fix it. At least until recently when I've started to wonder if continuing to use them is a smart idea even though there is nothing apparently wrong with them. I'm thinking in terms of a damaging (catastrophic?) failure particularly when the receiver is unattended. I'd appreciate input whether one should continue to use older equipment that can be inexpensively replaced.