Yes I was testing with small channels deliberately. Yes I know that is better to use larger channels. Yes I know that are also commit_fees involved in the limit of a channel.
A channel is created each time an incoming payment isn't able to "fit" into your existing channels. I disabled that option deliberately, to test this scenario: refill at maximum the existing channels.
But even then a channel that still shows 10000 sats available to receive and is not receiving is weird.