you just stop caring about market cap.. its meaningless

as for calculating the underlying value of a coin, thats for another topic that has already been answered multiple times over the years on this form [use search]

we are meandering away from topic of sidechains due to conversations of valuations of different networks

but when it comes to side chains my view is if they are sidechains and 'layers' of a main network. the different unit of measure on the subnetwork to the mainnet should be a fixed/stable peg, to easily get in and out of the networks without loss of value....
as appose to altcoins that have de-fi exchange/bridges to mainnets which can have variable pegs and have their own 'market caps' and other value measures

in short: to be a subnetwork/sidechain (aka 'layer') they need to be fixed peg if using different unit of measure

thus locked value of bitcoin in a 'vault'/smartcontract would also be the value of the other sidechain unit. thus not offsetting/doubling/creating more 'market cap' valuation silly games people play to make bitcoin look less valued

for instance, (i have not researched much into it but just using it as conversation piece)
d5000 mentioned a 'STX' network coin.. which has its own market and in just 3 months has lost 50% peg to bitcoin (0.00003600->0.00001800) so i would not call that a sidechain/subnetwork of a mainnet, but instead just a bridge to an altcoin

though these weak 'federations'(colluding signers) are more of a security threat of centralisation, i would more conclude if something is a 'layer' (subnet/sidechain) vs bridge to altcoin, if the value peg is fixed or variable

if you lock in xxxxsats and later(without spending) cant get out your same xxxxsats due to some market manipulation of pegging, then your just playing with a altcoin

we are still in the era where buzzwords and network categories are not solid in description/type, but with that said if any side/sub network has a deviating peg where you cant guarantee you'll get out what you put in, people need to be aware of that financial risk no matter the buzzword used

as for you thinking its difficult /not normally possible, well if it involve third party 'federations' the simple question is do you get to be a significant signer or is it a 'not-your-key-not-your-coin' lock, which you deposited into

we need to solidify definitions to make it easy for people to understand financial risks of offramping/locking in/bridging to other networks
not with some undescriptive buzzword that has no meaning. but a word that in itself has a dictionary definition that explains what it does
EG instead of bridges and ramps.. words like locks and vaults

afterall what does the words side chain and drive chain really explain to the uninitiated just from hearing the word

the buzzwords need to easily explain if its a feature locked to one mainnet and designed purely to aid that mainnet and be able to easily jump back and forth.. or if its complicated whimsy between many networks where value can be lost and hard to get back to certain mainnets.. but the main need of the buzzword, is financial loss risk

Recently it seems a post was deleted in this thread. It was a quite long post, and it looked a bit like it was AI-enhanced, but I wasn't completely sure so I planned to answer at one of the questions which were made in the post and which is an interesting topic to discuss here.

The question I wanted to write about was the particular centralization challenges of sidechains.

The big problem when we talk about two-way pegs is, afaik, that sidechain nodes and mainchain nodes don't have a picture of the full state of each blockchain. And if they had, i.e. if all Bitcoin miners and full nodes had a full picture of the state of the sidechain, then the sidechain would basically become part of the main chain: all the data on the sidechain would have to be retrieved and stored by mainchain nodes, so no scalability benefit would emerge.

Most sidechain designs thus select a sub-set of mainchain nodes -- those nodes deciding about peg-outs (sidechainBTC -> mainchainBTC transfers) -- which have to be aware of both chains' state.

The centralization risks reside in the way these nodes are selected. In the case of static federations, the risk is quite obvious: the federation is a group of trusted nodes, like in Liquid. In sidechain designs based on Proof of Stake incentives, like Nomic and tBTC, the risks are similar to those of PoS blockchains: not only "the rich get richer", but also there is the weak subjectivity problem, which means that new nodes need to "ask a friend" about the last trustable state of the sidechain, and these "friends" also become trusted intermediaries which need to be protected from identity theft and hacks.

Drivechain is the design which in my opinion has reduced the centralization risk in the best fashion: the subset are simply a subset of mainchain miners who must agree with each peg-out. Miners have excellent connectivity and hardware so they are quite well equipped to be able to follow several sidechains. But Drivechain is still in alpha state and the problem is that the miner group responsible for peg-outs is a subset of miners, it isn't possible to force all miners to participate.