It's probably technical - this is exporting to external calendar apps. I think it's perfectly plausible that a large number of broadly used calendar apps just d

It's probably technical - this is exporting to external calendar apps. I think it's perfectly plausible that a large number of broadly used calendar apps just don't support HTTPS imports, and probably fails in desperately graceless way - and so the decision is between supporting the feature insecurely, supporting the feature securely, but dealing with tons of customers, many of them both paying and technically unsophisticated experiencing a failure that they ascribe to TripIt and maybe do, maybe don't contact support about - or not supporting the feature at all.