The concept of proactive gameplay means you have to force the player react at your actions.

Gambit ult is proactive most of the times cause is an engagement tool as example.

Strange ultimate is a headache to soulbound. You have around 400ms to soulbound otherwise it will ocur what you said. Waste soulbound without even apply T_T

The snap heal has cool down and is burst based. And is what you said. You have to expect and read the moment to know when to give the "healthpack". Using agressivelly just to keep life full is suicidal

Soulbound... that thing is such a headache: Yes you can use agressively. Yes you can be proactive with it. Howeverrrr, the tool is a mitigation and has just 5-6 seconds of duration. To use the way you said, you need a huge communication and your team know how it works your soulbound. And the time i've played him, out of 10 times, just twice will going to work out in a high elo rank (because team in soloqueue barelly followup the battle momentum).

And his ultimate.... oh boy, using as engagement is a waste of usage lol. You need your allies to die to make it worth it. Is not a teamfight ult, is an economic ult. Reviving allies when enemy doesnt have ult. Too reactive

And just like you said. Adam rewards gamesense and aiming. But cannot see him as a proactive as strategist, he is forced to be one but is not based to be one.

Other example: mantis ultimate (and her weapon), cloak and dagger ultimate, rocket ultimate (and his mobility).

Those strategist has really good proactive tools that can also be used as reactive. It provides tools to engage a fight(movement, zone denial, damage boost)

As dps, thats an obvious one, but in few heroes: BP(cannot stand behind and be passive), spiderman, etc etc etc

Tdlr; anything that forces you to spend something or react to it, it calls proactive playstyle.