Seen some people talking back and forth on this, basically I'm with folks who are impatient about whether there are male viera/what they'll look like but honestly I think this'll work out based on track record. While it's not perfect, SE does pretty well about paying attention to fan demand and making stuff that a significant number of people are hyped for. After all, that benefits them and can get more players. It sounds like both in Japan and abroad people really do want male Viera, and what's more I think they know that between FFXII and the foreshadowing of FFXIV people are in heavy suspense about it. I think revealing female Viera alone first is most likely a tactical move to ramp suspense up so that when they do reveal males people are even more ecstatic and spread the word a lot.
The reason I'm so confident males will end up in the game is frankly because female Roegadyn and male Miqo'te are in the game when they initially weren't. When they weren't there it bugged people, and when they were allowed it got a very positive reaction. Male Miqo'te have been featured with reasonable prominence in the game too, there have been a solid number of male Miqo'te NPCs. Same with female Roegadyn. And what's more, player base I've seen way more female than male Roes with a roughly even number of male/female Miqo'tes.
If male Viera weren't in the initial release of Shadowbringers, honestly that's an obvious thing that would dampen enjoyment/excitement for a lot of fans. Not the reaction SE wants. If they did a belated release of male Viera it would stagger the interest and possibly make less impact for being spread out since not as many people would be paying attention after an initial disappointment of no male Viera upon initial release.
They have confirmed been planning out male Viera from concept art too. It has definitely crossed their minds that this would be useful to include in FFXIV. It's just a question of when we get confirmation and what that confirmation looks like imo.
Also. If they do go just as fanservice-y for males as they do females, that's gonna be a bit of a gamble on their end. While SE is pretty awesome about allowing male fanservice in games, having a whole race (and possible trailer) where that is showcased would be newish ground by comparison to races where it's just female fanservice. It'll be interesting to see if they go full speed ahead with it or play things more cautious.
(And I could be wrong on all of this of course, just me speculating.)