Is GRPN going to zero or maybe just maybe undervalued?

GRPN is an interesting stock. It ebbs and flows with the annual public sentiment towards services like GRPN and the performance of its competitors.

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• Revenue declining year on year https://imgur.com/a/yIbOSjL, peaking in 2014
• -60% vs S&P 1y, -76% 5y
• They hold 2.4% of SumUp's stock vs. an anticipated 5%
• But a recent slashing of marketing spend on a path to profitability

I don't see it going to zero tomorrow but would anyone be surprised to see them wind up operations in five years citing market trends shifting and become obsolete?

Why can't a competitor just replicate everything in GRPN's inventory tomorrow?

I can't see any bull case at all apart from a few % points if a catalyst materialize. But that alone makes it a sell. What am I missing?