Emissions regs written by people with no experience - not true, my perspective from the manufacturer side. Lots of discussion among the manufacturers and people writing regulations about what can be done and what timeline. Things written into the regulations about getting credit for engines built significantly better than required and using those credits to continue selling engines not meeting the standard so all models didn't have to be changed at once. We in the industry were integrating computers into our machines long before the first Tier 1 standard became effective in 1997. Today's Tier 4 standards were set in 2004 with the first Tier 4 implemented in 2012. By the time Tier 4 was set, engine companies had a lot of research and bought into the timeline. They were not numbers pulled out of the air. Some companies ran into snags when they discovered their planned methods didn't pan out as expected. From the industry side, there was a lot of customer input as to what they wanted in their future purchases and a lot of the input dictated computer controls whether the EPA standard was dictating they were needed or not. For me, I could manage my test fleet from wherever I was using my laptop to download the data, including fault codes, every day. That ability is not built into smaller tractors but its how JD can shut down tractors and combines stolen from Ukrainian farmers, and the same can be done for tractors and combines (of the higher end units anyway) stolen in North America.