Hi welcome to the forums,
you seem to be pro-conspiracy theory
but you bring up some good points. What you don't seem to understand is that aMSN is open source and with very limited resources, we only do what we need/want to do and no developer seems interested in encryption, so we never wrote anything for it. I had a look once at OTR and it seemed complicated to write and I didn't want to do it. All these encryption solution are contributed by users.. someone wanted to use simplite and he gave instructions here, as simple as that.. someone else wanted GPG encryption and he wrote the Kryptonite plugin. If you are interested in OTR, then by all means, write a plugin for using it, noone is preventing you from doing so, on the contrary, we'd be glad to have an OTR implementation.
If you really want security, I suggest you move to jabber, but if you want to keep in touch with your MSN friends that do not wish to move to jabber, then you can either use the Kryptonite plugin (only amsn to amsn support) or pidgin with OTR, or implement your own OTR plugin for aMSN.
