I like to consider "growth" and "maturity" as different things. If the public capacity is growing, it doesn't necessarily mean that this new liquidity is very useful. For example, a new node could open hundreds of 1BTC channels and never create inbound liquidity and never spend anything on LN.

This node's actions would increase network capacity, but it would actually be a net drain on network resources. Other nodes would attempt to use these channels for routing, but since there's no inbound liquidity on this node, every payment will fail.

Collectively, nodes and wallets could waste years of time trying to use this doomed node as a router.

On the other hand, an efficient routing node may have dozens of unused channels. They might decide to close these channels since they aren't earning anything. This action would decrease public capacity, but it makes the network more efficient/mature. Further, since channel liquidity flows both ways, a tiny network with high transaction volume is more efficient than a large network with low tx volume.

LN is an evolving network that has cycles of growth and cutting (kinda like a body builder). This is what makes the network as a whole valuable, thousands of economic agents using their local knowledge of payment flows to invest in more efficient ways to pay one another. It's messy, opaque, and chaotic but this is what makes LN immune to death by 1000 forks.

A forked LN network wouldn't have the same exchange-rate-adjusted value as the original LN. There is dense information packed into the network topography. Information about who wants to pay who, etc.

A forked network wouldn't have the same payment needs as the original LN. Some nodes wouldn't respect the new fork, etc. Forking LN would essentially lose all this built up efficiency (compressed information about payment flows) expressed in the channel topography and the forked network would have to start fresh and evolve its own effective channel topography.

That chart is showing ONLY the PUBLIC nodes and channels. But you are missing out another important aspect: LN is having 2 types of nodes and channels: public and private (unannounced). LN is much bigger than what you see in those charts.

Here is a guide about private nodes https://darthcoin.substack.com/p/private-lightning-nodes

No, you can't know exactly how big is LN. And that is kind of good thing. More privacy.

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

It could be the spike in fees that is stopping people from opening more channels.

More people are adopting custodial lightning as it just works better.

Hopefully we get more competition in non custodial lightning wallets as they improve