As cars without a carb pretty much do not have a choke, they do not have a choke sensor nor is there an equivalent in Bosch LH 2.4. Also I think something got lost in translation from the neighbor or he is an idiot.

Your issue is that the car either not sensing how cold it is accurately or it cannot supply the correct amount of air for an accurate start-up. Three causes come to mind starting with easiest to the hardest to work on:

The combination of dirty throttle body, misaligned or fault throttle position switch and someone like you neighbor adjusting the throttle stop screw thinking they were adjusting the idle. The FAQ's have a very good explanation of the basic procedure for this and it only requires the most basic of tools. Any chance you have a higher that 750-800 rpm idle once warm?

The IAC has is dirty (or failed but this is unusual). This is less likely but so easy to clean it is kind of a no-brainer since it should be done about every 50-100K miles anyway. Any chance you have a wavering idle particularly when cold (up to about 1200 rpm then drops to almost stalling before recovering).

Coolant temp sender is bad. This is a real pain to replace but if your car thinks it is 90 f degrees when it is actually 14 f degrees (what is "cold" starting in your instance?) it will not activate the extra fuel injection pulses needed for a real cold start. The lifespan of these sensors seems highly variable (or folks are replacing them when not their actual problem) but it seems universal that the Volvo or Bosch sensor is well worth the premium...and testing the variable resistance of the sensor before going through the trouble of installing is good insurance.