The canonical MicroPython connect idiom is `while not wlan.isconnected():
pass` — a pure Python busy-wait, and most gallery WiFi examples use it.
The emulated CPU only fast-forwards through WAITI idles, so a busy-wait
pins the sim at real execution speed (~2% of the chip in a browser tab).
Measured on the classic-ESP32 engine with a marker-bracketed harness: the
connect+DHCP phase costs ~1.5M busy instructions under a sleepy poll loop
and ~194M under the busy-wait — same firmware, same radio, 130x apart.
At browser speed that is close to a minute of wall clock for the connect
alone, which reads as "WiFi hangs" and got diagnosed as exactly that.
The proxy now sleeps 20ms per unanswered isconnected()/status() poll,
turning the user's busy loop into an idle loop without touching their
code. Re-measured end-to-end with the real prelude: 226.8M -> 64.3M busy
steps, and the made-up-SSID example connects with a 10.13.37.x lease on
the in-browser engine.