First of all you are right private channels are not taken into account so the real size of the network and its changes are difficult to grasp. For example, all channels between the Phoenix wallet users and ACINQ's node is not known, but it may represents dozens or hundreds of BTC.

Concerning the lack of growth otf these last few months on the public part of the network, it can indeed shows a lack of demand for more liquidity as the network is big enough to sustain the actual demand. We are in a bear market after all, and few new users are coming in the space so I guess it's not so surprising IMO.

What I can witness outside of these metrics though, is that the lightning development and ecosystem seems to grow at an exponential rate. The number of companies and services created around it seems outstanding and I'm very bullish on LN, even if I'd like to see more evolution of the self custodian lightning wallets side (better UX, better explanation of the fees and working of the channel part, better privacy). But this will come I'm sure in a near future with async payments, PTLC and blinded path etc...The LN network could then become as permission-less than the actual ethirium mainnet which would be good enough I think