AT skis are tools for the mountains, splitboards are toys, tele falls somewhere in between. I've had all 3, and have consolidated to just AT.
I will probably never ski as well as I snowboard, but it didnt take me too long to realize the limitations of my splitboard, and move over to the dark side for backcountry use. I may buy another splitboard when I get a real job, but for now I am totally happy to snowboard in resorts and ski in the backcountry.
I may have liked Tele more if my boots fit, but the classic duckbill still has way more limitations for climbing. Plus, tele is f'in hard compared to downhill or snowboarding.
Snowboard boots are the worst of all for climbing (hardboots seem to eliminate any benefit of snowboarding in the first place).