Zcash has been crashing for a long while, and stealing 20% of the economy outright is a large part of the reason. Yes, it motivates the miscreants, but that does not imply success.
Marketing also matters.
So honest marketing matters very much. The point of marketing should be to attract attention to useful features of Monero and increase its usefulness by promoting its adoption by third parties that add value (such as wallets, exchanges, merchants, etc.)
The seemingly principled idea that focusing only on tech, and not strategic promotion and collaboration, has resulting in the under adoption or stagnation of many promising technologies.