Fair enough! The part that always stuck out to me is that there were other potential designs that could have been made around how (and which) lifetime informati

Fair enough! The part that always stuck out to me is that there were other potential designs that could have been made around how (and which) lifetime information would be specified. I think sometimes people might not realize that the we didn't get stuck with the requirements we have for lifetime annotation today due to validation requiring exactly that set of information or an indifference to the burden it might place on the programmer to specify it; the developer experience was at the forefront of deciding how this should work, and as you say, weighing all of the factors that entails is a balance.