I think it's a little unfair to scrutinize the tweets of the devs, they aren't a source of official news - this is just the devs having a bit of fun among themselves. It's nice to see their tweets when there isn't much in the way of news forthcoming, but that is it.
I would also say to keep having hope and remain positive. BioWare likes providing different takes on romance in each game. Some LIs have shared similar traits but they have always been unique and brought something new to the table. I think Blackwall still has a good chance.
Maybe we can speculate on what his first name is? I still find it amusing we don't even know that 
Anyway, keep having hope guys! I shall pass out hugs and cookies to anyone who needs them 
Juuuust gonna leave something I typed earlier today on my tumblr in response to being tagged in reblogs of premature fatalism, because I'm lazy like that 
I read the exchange as facetious, especially in light of lore details that we already know from even as far back as DA:O regarding Grey Wardens:
Taking these into account, I easily read the tweets as jokes in expense of his older age, implying that stereotypical regular older folk would rather relax on their rocking chairs out of harm’s ways, comfy in their cotton jammies and fitting sandals, sipping warm tea, etc etc. Which is the total opposite of what we know of Blackwall's character so far from Sheyl's interview about him.
Of course, when you gotta explain the joke...welp. Not that it was our joke to share in to begin with.
At this point, everyone's just desperate to mine any information, whether it's to confirm their own opinions or disprove another's. Expect this to go on repeat until release, or when someone official finally decide to spill the beans before then.
I'm just gonna sit in this corner doing work (and getting antsy waiting to see GOTG on Sunday) while occasionally side-eyeing in the direction of Marketing.