I acknowledge that there is a lot anyone knows only because people studied insects which have been killed to make pinned or preserved displays, or insects which have been placed in contrived experimental conditions. What I know now depends on scientists engaging in practices that I don't want to opt into. That is why I link to the resources I've used to test my hypotheses and relate what I've seen to established knowledge about insects. As someone who doesn't have any goals or deadlines regarding this stuff (I'm just bugwatching for my own interest), I ask myself: What kind of questions need answers, and to what end? What more would I need to understand about insects which can only be understood if I snuff out an insect's life, or torture ki in a contraption to test ki's reactions? There is a lot I can know by looking without touching.
However, regardless of whatever I determine I "need" to understand, insects clearly want to live on their own terms without interference. That is good enough reason for me to take care not to deprive them of life and freedom, because it is really easy for me to do that as a relatively enormous human animal.
If there were widespread recognition that insects have their own desires, what kinds of questions would people studying insects even *want* answers to?
If you have a hunch about why insects are behaving as they do, can you find out without interfering with them? Can you live with not having that hunch confirmed? A controlled experiment expedites knowledge in a sense, reducing the amount of time you "have to" spend watching an animal to understand one particular thing about it. If you could take more time to watch insects where they are at, acting naturally, what more could you understand? Maybe the specific answer to one specific question isn't that important.
Some insects seem unbothered or at least tolerant of my presence while observing. Sometimes, they seem too occupied with feeding or grooming to care. Other times, they realize I am there and respond by moving out of view or communicating displeasure or a threat. Ladybugs and other beetles often run, purposefully scuttling to the underside of a leaf where I cannot see. Bees feeding on flowers will fly away and occasionally fly at my face. A good crisp photo of an insect is a nice thing, but disrupting insects to the point where they have to waste energy fleeing/fighting you is not worth it.
I take notes on insects I see. I write down ID guesses and identifying information (appearance, time of day, behaviour, interactions with plants and other animals). I take photos, but sometimes it's not possible to get a good one and it's better to observe with my own eyes rather than waste time getting the camera to focus.