Not sure how or why yet but since disabling the UART the ESP hasn’t missed a beat, 36hrs and counting.
Very odd but welcome 
What do you exactly mean by “disabling UART” ?
On your code only logger used UART (which you didn’t use to get logs).
Please don’t capture serial logs so you and us never need to know 
I read a lengthy thread regarding that particular ESP and poor wifi when powered via USB. The end result was that disabling the UART by snipping pin 16 fixed the issue. The other way was to power the board directly via the pins 0v & 5v - this had the same effect as disabling the UART.
It’s all experimental and for the sake of a couple of quids worth of suspect ESP I gave it a try; since then the board has not dropped out once.
I know I didn’t get the logs, my apologies but it would have meant keeping it connected via us to my laptop which i have to use in the day at work.
Maybe I’ll spin up another ESP and PN532 just to see if it replicates, maybe then I can get the log.
That’s the “unfamous” board design I mentioned earlier.
Just snipping a pin 16 doesn’t sound like ideal fix to me, why don’t you simply power it via pins.
Otherwise you will need to do extra steps every time you need to flash the board via serial.
Yeah not ideal but neither was cutting the USB plug off a PSU.
I probably won’t use this board for further updates if OTA fails, it’s proved untrustworthy so no point.
Currently reading the thread on best ESP boards…
Good. So you don’t end up with the other infamous board (C3 supermini with antenna and oscillator almost touching each other).
Most of the esp32 boards are pretty ok anyway. Look for some “brand name” ones or buy from Amazon something that has good ratings.
DOIT, diymore, Waveshare, Xiao …
Ahh bloody hell just got one off Aliexpress and It arrived today.
Use it for something that doesn’t ask too much. Near to router, low power settings for tx. And good luck.
I personally got one of those , the only Esp I have ever had that died by himself. Without warnings or explanations.
5 days and it’s not missed a beat, I’ll call this one fixed I think. Thanks for all the help.
On the topic you were searching, someone placed a switch on the circuit. That’s way more elegant, practical and sustainable approach.
Had ESP32 c3 supermini up and running a few days and very stable wifi so far. Plan is to use with deep sleep outside and lower radio output power to run some of my solar powered plant pot watering setups. Previously been using my stock of bare bones ESP12F for that.
Glad to hear OP got his ESP running better.
Most of superminis are just fine, OP was using Wroom32 though.
I wouldn’t use any $1.99 esp32 for anything that has to be reliable, like irrigation.
Maybe after long term test trials..
Oh, looks like nice place to live! What is approximate geographic location (without home address)? 
Nice. I thought it’s raining much more there.
Only rains twice a year. 6 months each time. The further west you go the more it rains.