Why do Cessna not just start manufacturing the 152 again with a 912is up front, there is a market for it!
LSA in certified form like the Sportcruiser and Tecnam are great fun aircraft to fly and learn in but they lack the robustness of more traditional trainers like the 152. If you are doing 500-600hrs a year in an LSA in a training role it will have durability issues. Training aircraft are going to take a battering and the build needs to reflect that.