As dageshi said, yes if there is significant traffic.

When cycling, under such circumstances, I usually stay between two parked cars until the traffic is better (that is usually after a switch of traffic light to red). But again I try to stay in reserved lanes, much safer.

If they're going significantly slower than the average speed and there's a pile of traffic held up behind them... yes?

So if you're stuck behind a tractor, do you also expect it to stop by the side of the road and let all traffic pass? I'm sure many farmers would disagree with you there and tell you they've got work to do. I've never seen any tractor do that in fact.

Same goes for bicycles, they've got places to be. It's a means of transportation just like a car. If there is no bike lane, that's though luck for the cyclist (as it's a lot less comfortable) and for the motorists behind them, and a good reason for cyclists and motorists alike to argue for more bike lanes. Why should they alone bear the cost of shitty infrastructure (in time lost stopping by the side of the road every time a car is stuck behind them for +20s)?