I don't think there was any external manipulation going on, and I think the strange we saw in the trailer was the Doctor Stephen Strange. Strange has never been shown to be extremely cautious with magic. Stealing off limit documents at night, restoring the dark dimension pages, playing around with the time stone on an apple, using the timestone in the end of doctor strange 1 like it was free ice cream, and attempting to use the stone on enemies where it's not absolutely necessary like Maw. And we all know strange supreme gave no ***** whatsoever.
The only time strange has ever been cautious with magic is when its in regards to other beings (Loki/Odin) or in IW when it was a no brainer answer when Tony was requesting to go straight to the intergalactic warlord who wants to steal the stone. Outside of those two instances strange has never been cautious with magic. And in regards to the whole "barely knows spidey" thing, like other people have brought up, its a war survivor relationship. Additionally, moods in the MCU in general have been more relaxed for the masters of the mystic arts because it seems clear they're unaware of the whole timeline tomfoolery going on right now (at least for now). Dormammu has been traumatized into never coming back, Mordo seems to be keeping his head low, and there's no more time stone to look after. Hell even Wong has been mostly relaxed. Going on vacation to random snowy cities, finding time to cage fight in San Fran (with magic btw), and singing karaoke at a night club with Shang-Chi and Katy.