If you want big numbers of nodes then you'll have to make it as simple as downloading an app from the app store & running it on your phone. Few people are going to buy a dedicated piece of hardware such as a Raspberry Pi & install Umbrel (or whatever) & wait days for bitcoin core to download and then run it 24/7. Its already a challenge to convince people the need to own bitcoin then tell them that they need to store it themselves on a special hardware device & a metal plate to store the words. There's no way most people are then going to run a node too. Just not going to happen, which of course is why there's on 10k or so nodes running.