No, it's not just you.
Earlier in the week, was on a BP 150kw after a short journey to it, this was at around 40% SOC starting charge and was only getting 50kw. This morning a few days later at Gridserve Norwich on one of their 350s at 42%, got 59kw down to 49kw once hit 80%. This was after a 5 mile journey from the hotel, so although it was warm outside I'm guessing the battery wasn't warm enough on both occasions as later on I stopped on the A1 at Retford services on one of the 175kw Shell Recharges on the way home (140 mile trip), turned up at 23% and pulled 110kw straight away, I stopped it at 61% SOC and it was still pulling 69kw.
This is in a Born 58kw on 3.0 software.
If this still exists in a few years time when more and more folk get EVs, it'll be all over the Daily Fail about the stories of people not getting the advertised charging rates because of the lack of understanding of how it really works and the complexities.
Appreciate I'm replying a bit late.
What you describe is all completely normal in a 58kwh ID3/Born. I assume all other MEB platform cars are similar in behaviour but don't know for sure. The entire charge curve depends on what SoC you plug in at, even at constant temperature. If you plug in with a 58kwh model at 40% you'll never get a decent charge rate, 50-60kw is all you can expect. Conversely if you plug in at 5% it'll do 130kw+, pass 100kw at 30% and probably be doing over 80kw as it passes 40%.
Personally I have only ever seen the ideal charge curve (twice) plugging in under 12%. I've had well over 100kw a couple of other times, again plugging in around 7-10% ish - and on those occasions it was following the ideal curve by the time it got to 25-30%. A couple of times I plugged in at 19-20% and got up to about 100kw, but it was down at 90kw or lower by the time it reached 30%. Plugging in above 20% I've never seen more than 90kw peak I don't think.
The algorithm in the car that determines allowable charge rate for the charger is obviously pretty complex. In summary, if you want it to go fast, you need to plug in low.
It would be great if they could modify this behaviour a bit in a future software update. In Battery Life's recent ID3/Mégane 'race' he showed that while the Mégane has a very similar charge curve when plugging in low, it's better if you plug in at higher SoC because it seems to follow the 'ideal' charge curve whatever SoC you start at (assuming good temperature) rather than behaving like the ID3 does.