Performance issue WARNING (MainThread) [homeassistant.components.light] Setup of light platform mqtt is taking over 10 seconds

I’m building my system up from scratch for the 2nd or 3rd time and I’m slowly adding back lines from my saved configuration.yaml

I had opened a bug report elsewhere about the utility meter sensor (the error code, not shown here, asked me to open a bug report), but I was then told that my system had performance issues; so I set it up from scratch on a VM instead of a Raspberry PI3 and now I’m already seeing these performance issues (I haven’t added any utility meter sensor yet)
I’ve only added lights, switches, and some sensors and I’m already starting to see performance issues like

2021-04-26 15:59:06 WARNING (MainThread) [homeassistant.components.light] Setup of light platform mqtt is taking over 10 seconds.
2021-04-26 15:59:06 WARNING (MainThread) [homeassistant.components.switch] Setup of switch platform mqtt is taking over 10 seconds.
2021-04-26 15:59:07 WARNING (MainThread) [homeassistant.components.binary_sensor] Setup of binary_sensor platform mqtt is taking over 10 seconds.
2021-04-26 15:59:07 WARNING (MainThread) [homeassistant.components.sensor] Setup of sensor platform mqtt is taking over 10 seconds.

Is there an issue with connecting to your mqtt broker?

no, no issues connecting to the mqtt broker (mosquitto)

àdditional errors just appeared
2021-04-26 16:04:19 WARNING (MainThread) [homeassistant.components.light] Setup of light platform mqtt is taking over 10 seconds. 2021-04-26 16:04:19 WARNING (MainThread) [homeassistant.components.switch] Setup of switch platform mqtt is taking over 10 seconds. 2021-04-26 16:04:19 WARNING (MainThread) [homeassistant.components.binary_sensor] Setup of binary_sensor platform mqtt is taking over 10 seconds. 2021-04-26 16:04:19 WARNING (MainThread) [homeassistant.components.sensor] Setup of sensor platform mqtt is taking over 10 seconds. 2021-04-26 16:15:52 ERROR (MainThread) [homeassistant.components.websocket_api.http.connection] [139740500671696] Client unable to keep up with pending messages. Stayed over 512 for 5 seconds 2021-04-26 16:15:52 ERROR (MainThread) [homeassistant.components.websocket_api.http.connection] [139740577300192] Client unable to keep up with pending messages. Stayed over 512 for 5 seconds 2021-04-26 16:15:57 ERROR (MainThread) [homeassistant.components.websocket_api.http.connection] [139740500671696] Client unable to keep up with pending messages. Stayed over 512 for 5 seconds 2021-04-26 16:52:32 WARNING (MainThread) [homeassistant.components.webhook] Received message for unregistered webhook 1215d33a66513cd002fe37c0f91ff2ae69bb24a7a54132a2c647b8a3488546ca from 192.168.0.154 2021-04-26 16:52:32 WARNING (MainThread) [homeassistant.components.webhook] Received message for unregistered webhook 1215d33a66513cd002fe37c0f91ff2ae69bb24a7a54132a2c647b8a3488546ca from 192.168.0.154 2021-04-26 17:04:14 WARNING (MainThread) [homeassistant.components.webhook] Received message for unregistered webhook 1215d33a66513cd002fe37c0f91ff2ae69bb24a7a54132a2c647b8a3488546ca from 192.168.0.154 2021-04-26 17:04:15 WARNING (MainThread) [homeassistant.components.webhook] Received message for unregistered webhook 1215d33a66513cd002fe37c0f91ff2ae69bb24a7a54132a2c647b8a3488546ca from 192.168.0.154 2021-04-26 17:06:38 ERROR (MainThread) [aiohttp.server] Error handling request Traceback (most recent call last): File "/usr/local/lib/python3.8/site-packages/aiohttp/web_protocol.py", line 422, in _handle_request resp = await self._request_handler(request) File "/usr/local/lib/python3.8/site-packages/aiohttp/web_app.py", line 499, in _handle resp = await handler(request) File "/usr/local/lib/python3.8/site-packages/aiohttp/web_middlewares.py", line 119, in impl return await handler(request) File "/usr/src/homeassistant/homeassistant/components/http/security_filter.py", line 56, in security_filter_middleware return await handler(request) File "/usr/src/homeassistant/homeassistant/components/http/request_context.py", line 18, in request_context_middleware return await handler(request) File "/usr/src/homeassistant/homeassistant/components/http/ban.py", line 72, in ban_middleware return await handler(request) File "/usr/src/homeassistant/homeassistant/components/http/auth.py", line 129, in auth_middleware return await handler(request) File "/usr/src/homeassistant/homeassistant/components/http/view.py", line 129, in handle result = await result File "/usr/src/homeassistant/homeassistant/components/websocket_api/http.py", line 42, in get return await WebSocketHandler(request.app["hass"], request).async_handle() File "/usr/src/homeassistant/homeassistant/components/websocket_api/http.py", line 233, in async_handle await self._writer_task File "/usr/src/homeassistant/homeassistant/components/websocket_api/http.py", line 81, in _writer await self.wsock.send_str(message) File "/usr/local/lib/python3.8/site-packages/aiohttp/web_ws.py", line 300, in send_str await self._writer.send(data, binary=False, compress=compress) File "/usr/local/lib/python3.8/site-packages/aiohttp/http_websocket.py", line 687, in send await self._send_frame(message, WSMsgType.TEXT, compress) File "/usr/local/lib/python3.8/site-packages/aiohttp/http_websocket.py", line 656, in _send_frame await self.protocol._drain_helper() File "/usr/local/lib/python3.8/site-packages/aiohttp/base_protocol.py", line 87, in _drain_helper await waiter File "/usr/local/lib/python3.8/asyncio/selector_events.py", line 935, in _write_ready n = self._sock.send(self._buffer) BrokenPipeError: [Errno 32] Broken pipe`