I beg to differ. There are ECUs on the market that can do more than any factory ecu with regards to engine controlability. The communication aspect between different modules isn’t there yet like OEM stuff but really isnt needed. Some do have CAN networks that rival manufacturer level stuff. Some of the common ones by Haltech, Holley dominator, and the former AEM infinity (now owned by Holley which is why their tech is so advanced now) as well as a few others would blow your mind with how capable they are. I’ve tuned (and currently own and tune) both factory ECUs with programs like HP Tuners as well as AEM infinity and have done a couple Holley ECUs for other people and for what we are interested in with our hotrods, the aftermarket efi stuff is incredible. If you break down and don’t know how to read a datalog or figure out which sensor isn’t communicating with the ecu that’s on you, It’s super easy comparatively speaking.