I completely agree that subscription charges for a service you signed up for and could have, but didn't bother to cancel is not a valid chargeback. If you initiate one and complete the interview questions honestly I think the chargeback would actually not be allowed. (Do you recognize the merchant? Yes. Did you approve the charge? Yes. Did the merchant deliver the product or service? Yes. Hmmm... Sorry, we can't refund your money)
However there is a slippery slope. Two examples that hit me recently, an iDrive renewal where they refused to tell me the renewal price and their online form provided no way to opt-out of the renewal, their online chat told me to call a phone number, and it turns out the price was 10x the first year cost (and not at all competitive with any other backup service). Another was BitTorrent Sync which was supposed to be converted to a one-time license but then lo-and-behold a year later another charge showed up.
But for merchants that provide the ability to cancel a subscription online, and who let users know before an annual charge is about to hit your card, I agree the customer has some responsibility to manage their subscription.
My personal opinion is that monthly recurring billing can send invoices after the charge or even no email at all if charges are the same amount every month. Annual recurring should email a week before the charge to remind a customer it's coming, or should allow a full refund of the charge if contacted within 30 days of it hitting. For example LinkedIn refunded an annual recurring charge that I contacted them about within a few days of it hitting the card for a "subscription" I didn't actually want and it just took a single email to sort out.
In any case, if I signed up online I must be able to cancel online with a click. I won't play games with merchants who have dark patterns that make me jump through hoops or pick up a phone to manage an online subscription. These merchants deserve the extra chargebacks they get, and they know exactly how they could reduce their chargeback rates. They've just done the math and found the dark patterns unfortunately are net-profitable.