Everyone bought PowerPlay - not just those who enjoy direct PvP - and it was consciously implemented in all three game modes.
You really need to stop making this argument. Frontier has "consciously implemented" a lot of things one way, and has since recognized them as mistakes, and changed them. Just the history of Powerplay from 1.3 to 3.0 has had the following changes/discoveries:
- Consolidation was added as a mechanic to counteract people deliberately Preparing terrible loss-making systems. This behavior was unforseen at 1.3 and has since been (partially) addressed.
- The practice of placing Expansions into enemy space to deliberately contest CC was unforeseen.
- The practice of only redeeming Undermining vouchers (known as sniping) was unforeseen.
Your argument assumes that Frontier is infallible and never makes mistakes in game design. As a long, long list of patch notes could attest, this is definitely not the case. Either come up with some justification to keep Solo/Private Powerplay that isn't "it was deliberately done that way in 1.3".