I think there are some popular misconceptions about behaviour management which prevent people from understanding how gentle parenting could work.
The first big one - the idea that all behaviour must be addressed otherwise it will get worse and worse exponentially. Thinking that what you let go at 2 will be twice as hard to deal with at 4, what you ignore at 4 will be twice as hard to deal with at 8 and by 16 you'll have a juvenile delinquent.
This is (in many cases, not all cases) incorrect - a lot of behaviour is developmental and if you do nothing, they will grow out of it anyway. Especially if you build other skills around it. For instance, the idea of making sure that you always punish a tantrum by exclusion or ensuring it doesn't lead to the wanted thing or ignoring, being that if you don't do these things, then the child will still be tantruming at 4/6/8/12. But this isn't the case as most modern parenting methods say don't punish tantrums, they are age appropriate expressions of overwhelming emotion. And yes of course you shouldn't immediately and consistently give a child whatever they want when they have a tantrum to get them to shut up - as that probably will teach them it's an effective method to get what they want - but you don't need to deal with it punitively. If you validate a child's feelings and soothe them and help them calm down, then have a conversation about what they want and decide (independent of the tantrum) whether it's a reasonable thing for them to get or not, they do still grow out of tantrums and stop having them - they don't just exponentially get worse and worse. In addition talking about their feelings allows them to develop the skill to express those feelings in a less explosive way.
The second big misconception is that the only way to enforce a boundary is by using threat of punishment. That is one way to enforce a boundary and it can be an effective one, but it's not the only way.
Baby is waking up so I can't do specific/comparative example - but quickly -
Prevent the action with a physical barrier
Remove child from situation so that they can't do the thing
Remove whatever it is they are trying to do something bad with
Redirect them to an acceptable way to fulfil the urge that they have that isn't destructive
Close supervision and jump in with intervention before something happens (talk to them/steer them away)
Avoid a situation that it happens in
Change the environment so that it's difficult
Make the wanted alternative more appealing/easier
Although some of these might look like a punishment (e.g. take away hard toy that is being thrown) that's fine as the idea is not "never do anything the child doesn't like" but "do what is necessary to keep everyone safe/sane" and the point is you might take away a toy that is being misused temporarily, but you would not take away a toy to punish a child for spitting food, for example.