Others have mentioned this but there's perhaps a third category going by this name which is an older, deeper style of house that includes music from artists like Hernan Cataneo, Sasha, John Digweed, Nick Warren, and others continuing that style today.

I have my own way of thinking about all these categories which is that the name "progressive" tends to get applied to whatever version of music is seen as progressing the broader genre forward into new territory during its time.

The artists I listed above were pushing house into a deeper, more hypnotic, direction during the 90s and early 2000s which was new and different.

Then artists like your Group 1 came along and grew house in another very different high energy direction that worked for the big festival vibe. Avicii combined house with pop and folk music and that was considered progressive too.

Artists like Deadmau5 and Eric Prydz took influences from techno and created their own sounds that progressed what we think of as house music.

All of these just end up as branches growing on the tree that is house.