为什么Rails中的ActiveRecord不支持多表继承？

I was trying to implement a set of models I had put together on paper and ran into an issue where I thought the best way to go about it would be using a Multiple Table Inheritance setup. However, after google searching I found that ActiveRecord doesn't support MTI... even though there are plenty of articles showing how it can be done. This had me wondering if I was setting up my models correctly if it's not implemented. So my question is why doesn't Active Record have built in support for MTI? If you are curious to what my model setup was 'going' to look like I'll leave it below.I was trying to implement a set of models I had