The symbol isn't exclusive to Nazis, and the styling suggests it's something else...

I mean, it looks like the right timeframe, and they did use the swastika in that form, but let me go plug it into tineye.

checks

Yeah, it's the Nazis.

https://www.alamy.com/this-associated-press-photo-shows-the-swastika-during-rehearsals-at-berlins-stadium-june-20-1938-berlin-germany-the-stadium-will-again-will-be-filled-to-capacity-when-the-hitler-youth-and-the-sa-are-celebrating-summer-solstice-day-in-the-olympic-stadium-june-21-1938-berlin-germany-hundreds-of-sa-men-will-form-a-torchlight-sun-wheel-in-germany-on-june-28-1938-ap-photo-image525598168.html?irgwc=1

This Associated Press photo shows the Swastika, during rehearsals at Berlins stadium, June 20, 1938, Berlin, Germany. The stadium will again will be filled to capacity when the Hitler Youth and the SA are celebrating summer solstice day in the Olympic Stadium, June 21, 1938, Berlin, Germany. Hundreds of SA men will form a torchlight sun wheel in Germany on June 28, 1938. (AP Photo)

What would be a good assumption then? That they are a religious crowd of Hinduists/Buddhists?

For one, that kind of display is typical of authoritarian regimes. Also, Nazis ruined swastikas for everyone else so saying Nazis would be a good assumption indeed. And also you could've just looked it up like the dude replying to you, props to them.

It's always a good assumption that you're dealing with Nazis when you see a swastika. How much more do you need to feel good about your assumptions? That symbol hasn't been used by any other group since the Nazis. Yes, it used to be used by other groups. Those times are long gone.

I feel it’s not a good assumption.

Well, hopefully you learned something about that.