For small scale PV, the cost is so negligible and the benefit of uniformity is so large that everyone having the same rule is by far the best solution. Just ado

For small scale PV, the cost is so negligible and the benefit of uniformity is so large that everyone having the same rule is by far the best solution. Just adopting WEEE verbatim would solve it entirely and even if it is flawed, the problem is so simple the harms will be smaller than non-standardization and loopholes. No reason there can't be a per region method for the wind as long as it doesn't make them vulnerable to more powerful, hostile non-state entities (mining, tech companies, and fossil fuels is a fairly big precedent). The wind turbine industry is still fairly chaotic, but will likely become as centralised and powerful.