1979 kz650 Kickstarter not turning completely

I was out riding today and stopped for a couple of minutes. When I came back out to leave, I couldn't kickstart the bike. The electric starter hasn't been reliably starting the engine lately, so I've been kickstarting it which usually turns it over fine. I was confused about why it wouldn't start up after just having been working fine several minutes before. I decided to let it sit for a while and see if I could start it again later. When I went back to start it, after a couple of tries with the kickstart, it stopped rotating easily and eventually I couldn't completely depress the kickstarter.

Some other possibly relevant facts: the battery seems to be dying because the electric starter barely turned over near the end of the ordeal. I've recently changed the oil and filter and the level looks good. A few blocks before I stopped the bike, the shift lever was juddering a bit when I tried to put it into first gear as I came to a stop, but it went into gear fine at a complete stop.

As I was reading through old posts about similar problems it looked like folks thought that a kickstarter that was hard to move might be due to a seized piston, but it seemed to be running fine, with no new or concerning engine sounds.

I'm totally new to motorcycle mechanics so I hope this isn't too rambling with irrelevant information. Thanks for looking!

Could remove the spark plugs and see whether the engine may be cranked over by using the kick starter.

Am thinking about possibly of hydraulic lock-up due to onset of an issue with the carbs, whereby raw gasoline might have entered a cylinder.

Good Fortune!