There are reasons for push-vs-pull but one huge advantage of pull vs push is that you're less likely to get overwhelmed by useless metrics. You have to make a very deliberate decision to take the metrics you want. It also makes sense that the observer decides what to observe.

Also, if you really, really want push, there's always the push gateway in the Prometheus tool kit. Also, you can use Telegraf from InfluxDB with Prometheus.