Nuclear waste is hugely overestimated by civilians who know absolutely nothing about it.But deferral has worked so well for the nuclear industry, everyone should totally adopt it for all hazardous compounds because it is a 100% effective strategy!
Reality is the worlds entire nuclear waste stockpile sits at 250k tons including all levels(if its not high level its basically harmless btw). Reality is also that the entire high level nuclear waste stockpile can be reprocessed safely using currently existing technology.
To put it bluntly there is only stored waste because it is currently not cost effective to process it.
Most waste is graphene. Radioactive in a technical sense but you could burry this stuff in your back yard and never notice it because it wont break down naturally. Radioactivity isn't organic.. it has very simple control methods for 99% of it. The last 1% is problematic sure but I bet you also didn't know that many industrial processes spontaneously generate nuclear material waste sometimes either(wastewater usually). Pound for pound nuclear still produces the least amount of waste per year and nearly all of the high level waste is recyclable. No other industry beyond the asphalt concrete industry can really get near that level of efficiency in waste. Oh... and unlike other forms of energy generation the nuclear powerplants are required to deal with their own waste. Solar they just dump in a landfill and the power company laughs because its someone elses problem.
Silicon tetrachloride can be neutralized yes though it typically is burned(chlorine offgas) or neutralized chemically(extremely exothermic). The sad fact is most of the solar cell waste is not currently recyclable in the amounts required. By the time the waste buildup of panels reaches a critical point for the economics to catch up it will have wrecked whatever ecosystem it was currently dumped into for the next hundred+ years. Solar cells are a time bomb. Id rather deal with nuclear waste that 2 feet of water can contain indefinitely or the carbon/steel of wind turbines.