Doing PNP/CEC and All program draws depend on so much more than just international flights. I think IRCC is not working on a full capacity, and I assume processing FSWs is more demanding than CECs.
I also think they are doing this new method of alternating draws as doing only all programs would create a heavy backlog of people that process is stopped by different factors depending per country, like VFS closed for biometrics.
This method might not be ideal, but it is so much better than March-June with not a single FSW draw, or countries like Australia and New Zealand suspending their immigration programs until further notice.