Yes, I’m aware that solid state has been invented. While the tubes here will need eventual replacement, they are obviously user replaceable, so no technician needed for the most common “repair”. Although the overall design is 60 years old, they’re using modern caps here, so those should last just as long as any other quality amp.

But, because of the simplicity and long history of this product, there will likely always be a source for any needed parts and repairs, unlike most vintage electronics. Additionally, due to what it is (an amp, nothing more), there is no technology to become obsolete. How many perfectly operating A/V receivers are now useless due to changing technology? The Denon AVR5600 released in 1998 was the ultimate AV receiver and sold for over $5000. But… no HDMI, no 4k, no modern deciding, and today it’s virtually worthless.