I was looking into that recently, and the answer is yes, tiles are better. While tiles can't act as standalone insulation, they are better at trapping heat than a plain wall or a thin wallpaper.
There are many types of tiles out there. Both ceramic and porcelain tiles have low thermal conductivity, so they're great at helping to maintain a stable indoor temperature. That means you can trap valuable heat during the winter and keep the heat out during the summer. In contrast, paint and wallpaper do little to contribute to thermal insulation.
That said, there are special types of paint and wallpaper out there that claim to have insulating properties. Whether or not those products offer more insulation than tiles will depend on the quality of the products and on the types of tiles you're looking to use. But it's good to keep in mind that those options do exist.