It's a technical problem. There are technical solutions. When I want to make a BTC purchase, I spend XMR using xmr.to or shapeshift.io. Consequently my privacy is assured.
What's the technical solution for buying a car, a house, a commercial property?
In each of those cases, the purchase is a matter of public record, and hence privacy concerns are moot.
But yes, there is a scale problem. When the nickel and dime volume is large enough, then the liquidity will suffice for the dollar traffic to insinuate itself, &c. Given the trend in privacy awareness in marketplaces which have historically been early adopters of crypto, I expect the scale problem to work itself out over time. "Price fixes everything."
More like "price fixing screws up everything." The miners just want a good Return on Investment, as they should. The're not going to rock the boat, either for the blockstream patch, BIP101, or any other scaling solution until it hurts their bottom line enough to do so. That means the price has to go down far enough for them to have the incentive to adopt a patch and if price doesn't...fullblocalypse. Miners will take us right to the brink because they want the fees and don't want risk breaking Bitcoin until it's clear that it's already broken.
As fees creep up and most legit users stop using the network, the money launderers tax cheats and drug dealers will dominate and then the governments will push to seal up the on and offramps under some anti-terrorism bullshit.
Blockstream can stop BIP101. Bigblockers can stop Blockstream. Nobody has a consensus and nobody is going to get one. Traders will be able to jam the network for hours to manipulate the price. Meanwhile BankAmericoin, Applecoin, FBcoin and others are going to roll out their products and the first mover advantage will be squandered.