I guess in the near term dozens of specialized robots for each task will be necessary, but the idea I like is teams of general purpose robots using simple tools to perform almost any task "manually". It's too early to implement that now, but I think it will be feasible within my lifetime.
Generality is probably one reason why this robot sprays instead of hoeing. In addition to killing weeds, by changing chemicals this thing can fertilize, and they also mention pollinating and preventing pollination of flowers. (Preventing pollination avoids overburdening some kinds of trees. Currently instead people have to do "thinning" which is simply pulling half of the crop off the tree before it's ripe and throwing it on the ground).
One group I'm familiar with are using 50kv (and "more than enough" amps) for the purpose.
If people have to stay around to care for it, then yes, it's scary.
This is just a misunderstanding of the risks involved in various things.
That said, comparing a 50Kv shock to a handheld taser (which typically run at 300-500v) makes me think I might not be the one who misunderstands the risks.
You're off by three orders of magnitude. You need about 32 million volts per meter to overcome the resistance of the air. For a gap of a centimeter, it's about a few hundred kilovolts.
And I grew up farming, I'm quite familiar with the dangers.
For example harvesting equipment... the big ones are sort of up to a 30 food wide chainsaw with conveyors and other grabby bits to suck you in. People need to be many meters away from those things while they're running for any sense of safety. A hot spark has nothing on many other dangers and if designed with any sense would only result in severe local burns. Plenty of farm equipment will effortlessly rip a limb off if it doesn't tear your entire body into bite sized chunks.
You know the machines that do that and you don't go near them. When you're the operator you must know where everyone is at all times and know what they mean to do... and be able to communicate with them with a series of gestures, eye contact, short yells, etc. If you don't it's trivially easy to kill your helpers.
in my experience, this is the best approach. I worked at a few biotechs that did a lot of lab automation.
the robots that could do everything were hardly ever used because they did everything poorly and seemed to be constantly in need of repair.
the robots that could do one simple job were always in use.