Ask Netgear? They control the vertical, they control the horizontal, and they control the support (or lack, there of).
There is, however, in the larger industry, a different between EOL (End Of Life, which includes manufacturing and sales), and EOS (End Of Support, which would include firmware updates). Ask Netgear if they are committed to software/firmware updates going forward. The likely answer is yes, but only Netgear can provide a definitive answer (and only a Netgear customer has standing to ask the question in the first place).
All manufacturers (Netgear included) have moved products to EOL status when they don’t sell, or for which they have a new product soon to be released. Given the almost minuscule numbers of people wanting a COAM EMTA, I suspect they don’t sell (well).