Does it? It looks completely generic to me, replace the characters and the alien species and you could have any other franchise in there.

The trailer goes like: boringly obvious convo > spy movie flash cuts > obvious convo > obvious reveal > Liara! > boring fight scene where MC has no challenge (oh look, they used one ability!). There's nothing that could indicate this being a good successor to the trilogy, enough to warrant a 5. At least with Andromeda it was clearly a spin off. I don't see how this trailer gives any indication aside from Liara that this matters at all for the Mass Effect mainline story and universe.

Fans are just desperate, and on denial. Mass Effect is a trilogy, it ended with ME3. There are no further stories to tell on the main timeline.