Essentially, Ryan is telling conservative voting blocs in the House (and Senate, indirectly) to pass his proposal or have the consequences be on their heads, but that he won't allow it to be substantially amended.
Conservatives in the House, meanwhile, continue to kvetch that the AHCA is "Obamacare Lite" and contains Too Many Awful Things (like crippled efforts to make it affordable, too many people covered by Medicaid, not enough work requirements to let someone to the doctor) for them to support it.
Ryan's stated argument is that the changes the conservatives want won't fly with the Senate's budget reconciliation rules, meaning it would have to come to a normal vote, which the Dems would filibuster. His unstated argument, as the article notes, is that if the conservatives a too draconian, there are enough Senate Republicans who would defect to vote with the Dems to defeat it.
Again, this would all be much more amusing to watch if people's health and lives didn't hang in the balance.
Paul Ryan Rejects Major Changes to Healthcare Bill – The Atlantic
“It really comes down to a binary choice,” the speaker declared on Thursday, rejecting major changes sought by conservatives.
