With one exception; sometimes mesh routers include a dedicated radio for the 'backhaul' connection.
When my powerline networking sucked, I bit the bullet and bought a 2-node mesh WiFi system that is tri-band. The 2.4 and 5 GHz bands are used for my client networking, while the 6E 6GHz band is used for the intra-node backhaul. I plopped one unit in my garage near my back patio, and the other unit in the center of my home. I now get ~500 Mbps WiFi from my iPhone in my garage, standing in the exact same spot where I got 32 Mbps from my brand-new powerline kit (my phone screenshot is in the article).
Mind you, my mesh WiFi solution was more expensive than the powerline kit; it cost around 2x as much. On the other hand, it's more than 2x the speed and also improved the general wifi performance throughout my home and not just in the garage, so I think in terms of value per dollar I came out way ahead.