But, demand is created by early adopters (the people here), and those people don't use DEX because they don't use Samsung, due to Samsung being considered janky-to-insecure, depending on who you ask.
Marketing budget? Good distribution?
What technology-related point are you making?
If you ask a member of the Church of Apple, yes, you'll get that answer. Ask any heretic and they'll give different answers ranging from 'I want to keep things separate so I don't flush my PC down the loo next time I forget to take it out of my back pocket' to 'I want to keep my PC personal and don't trust ${vendor} to abide by that promise'.
As to 'Samsung' (or, rather, Android) being 'insecure' it is remarkable to see this premise being pushed. From what I gather there is not much difference between Android and iOS in 'security' - if anything it seems to be iOS which is more often in need of patching against yet another 0-day/0-click related to problems with iMessage or other text-parsing related bugs where Android 'security' problems seem to be more related to the lack of updates for older devices.
The market has already spoken.