Cisco, Juniper, and Arista make carrier hardware like cell phone radios and controllers and traditional telephone network switches?

While there's probably a little overlap in all of their product lines with Nokia (I mean Nokia makes simple ethernet switches so that carriers can buy all their gear from one vendor), most of those companies don't really compete in the same markets as Nokia

Cisco isn't selling into T-Mobile and AT&T's customer networks. Nokia isn't selling into JPMorgan's or Walmart's IP networks