I would never recommend putting yourself at risk, but ghosting the person after lying that you’d like to see them again is just a dick move.

There may be some impact, come July, when the third party apps stop working. However, I have to imagine that the vast majority of mobile users use the official app. Quality may take a hit, with the loss of some mods and mod tools, but Reddit will be just fine. Sadly, Reddit rates too highly on content, users, and resultant utility (for many communities) for most users to completely abandon it.