@marcoarment Following-up on the latest @atpfmAccidental Tech Podcast episode, my trusty Sennheiser HD-424X from the early 80s already had connectors at the earpiece level (although not standardized as nowadays).
Bought replacement earpads some years ago but seems they’re now very difficult to find (the product is nearly 50y old).
The hand band plastic is starting to get a bit sticky, so your other remark on plastic toxicity makes me a bit nervous to wear them again (which was quite rare these days anyway).