If you're thinking Drones like the Revenant, I think that's going about things wrong as it's still a "stand up" fight and doesn't quite mesh with the whole asymmetric warfare part.
I'm thinking drone support vehicles with booby traps strapped to them. Simple, cheap, available, fast to field, and exploits Warrior Caste prohibitions against civilian targets and the Society's superior E/W capabilities.
Maybe drone operated SLDF vees with Nova CEWS might work though...
That could work too, but would be more involved.
A car can be controlled with an RC system and some servos and linkages. (Just watch Mythbusters.) With no weapons -- only a bomb -- all you have to do is drive it close to an omnimech and press "boom".
A tank requires more. Its tracking/targeting/firing systems have to either relay data back to the operator or have some level of AI running them.
The Society certainly has the technical know-how to do the latter, but the former should require less time, resources, and facilities.
Once again, remember that the Society had limited time and resources.
I think that argues in favor of the Society using support vehicle drones with bombs. They certainly cost less and take less time to field than developing or manufacturing a new combat vehicle. And they might even be faster and cheaper than pulling an SLDF tank out of a Brian Cache and restoring it to operability.
They may not have had access to Drone tech in the first place,
There's drone tech and then there's DRONE TECH.
Caspars and Voidseekers are DRONE TECH -- AI-ish systems that could operate independently. Maybe the Society had preserved that SLDF technology.
But even if not, there's still canon drone tech like the Hi-Scout, NapFind, and PathTrack or the Bullet Suicide Drone -- remote-controlled systems run by a human operator. Even if the SLDF's AI systems were lost to the Society, remote controls were certainly well within the Society's technical capabilities.
not had the time or resources to bring a system even to limited production.
With support vehicles, I'm not talking about a factory production line. The Society didn't create one even for crewed combat vehicles.
I'm talking about modifying civilian cars and trucks in garages so they can be operated remotely and blown up.
plus it is worth pointing out too that drone tech actually doesn't reduce the number of warriors you need.
Sure it does.
If we're talking about AI, there's no human operator involved.
If we're talking about remote-controlled combat vehicles, you need one operator instead of several crewmen and that operator will probably survive more battles than those crewmen.
If we're talking about remote-controlled and -detonated support vehicles, you don't even need a operator with training on military systems. You just need a laborer or tech who can drive a civilian vehicle remotely and press the red button that goes "boom".
Besides which, this is the Society we're talking about. It's a lot easier for them to fill vehicle crews with drug-addled Bandits, civillian conscripts, warrior washots, slaves or whatever else. The workforce allready exists without the added expense
A human crew is always going to cost more to house, feed, and train (even in abject poverty) than an RC system and one operator.
of developing an advanced piece of tech to do the same job
Most of the Society's tech is an extrapolation of already developed technology developed in secret. Drones would have basically needed to be developed from (almost) nothing
In TacOps, "Drone (Remote) Systems" are available to the Clans and are mid-tech (rating C). Based on this, the Society should not have to develop much of anything.