It’s worth it as long as anyone (including you!) are willing to pay for it!
I have a website that I haven’t updated in years. It costs me about $50/year to keep online. I’m attached to its presence for no particular reason, it would actually cost me MORE money if it were visited. (It’s moniker, thisiswhyimfat.net, isn’t even really applicable anymore. Though I just had McDs for the third time in 3 days.)