In any case, a fork of Bitcoin with bigger blocks has existed for years and the market doesn't prefer it despite all the big names and companies hyping it up at the time of the split.
Satoshi left Bitcoin so there wouldn't be an appeal to authority so maybe your argument isn't as strong as you think it is.
If all you care about are transaction speeds then use the lightning network. Instant settlement of bitcoin and much lower fees. There are protocols like Cashu [1] that allow you to transact offline anonymously for no fees and settle on the lightning network.
Why do you need "diversity of assets to transact with"? Go to any store in almost any country and they usually accept a single currency. Maybe in some they take local + USD. You're arguing for something the market doesn't seem to care about outside of speculative trading for fiat gains.
And even if you really want stablecoins they've been added to bitcoin via the lightning network and taproot assets. Tether for example can be used via bitcoin [2]. There's a reason Bitcoin makes up well over 50% of the total crypto market.
You "can" do all these things on BTC. Almost nobody does. All of Tether & USDC usage takes place on other blockchains. The lightning network is notoriously tricky to use and isn't trustless. A diversity of assets enables things like PAXG, an ERC-20 token backed fully by real-world gold, as well as things like tokenized stocks, bonds, and t-bills, the last already existing, and the former surely coming in the near future.
Additionally BTC isn't "over 50% of the market", it's over 50% of the market capitalization, which is a huge difference. BTC doesn't have the raw TX speed to make up 50% of actual market activity.
Transaction fees have been about as low as they can possibly be for months. It costs roughly $0.15 to move a UTXO right now.
The people who argued for increasing the block size were making a tradeoff between decentralization and "low" transaction fees. Increasing the block size makes the chain grow faster which causes several problems: the time to sync new blocks goes up, initial chain download time goes way up, and block verification takes more CPU.
The parameters were initially set so that anyone could run a full node for as many years as possible which is the most important part of the ecosystem by far. If you make it harder for the average person to run a node it doesn't matter how cheap the transactions are if ultimately a small group of people are capable of running it. You could argue that doubling or quadrupling the block size doesn't hurt decentralization, and maybe you're right, but that also doesn't move the needle much for transaction throughput either at least not enough to make a difference for adoption.
Bitcoin can and should be scaled in layers. The detractors are just impatient.
While it's not here yet, Vitalik's future plans for Ethereum involve making it possible to run validators on smartwatches[1], which is far more accessibly decentralized than BTC could be and far more possible with Ethereum's PoS consensus as opposed to PoW, without needing to cripple transaction speed to boot.
There are methods that make it feasible to train models over the internet. DiLoCo is one [1] and NousResearch has found a way to improve on that using a method they call DisTro [2].
There are ways to combat spam that still allow for anonymity.
One example is proof-of-work. You can require a submission do 3-5 seconds worth of work on typical high end laptops/phones so that it becomes cost prohibitive for someone to post thousands of submissions an hour. There are ASIC resistant algorithms to prevent spam-for-hire services that might try to game the system.
Most users are passive consumers of content anyway so they wouldn't notice this process and when they want to post a few times per hour or day then the 5 seconds lag will be worth it to have a better social experience.
The fentanyl crisis should serve as a warning here. Precursors can be made in labs elsewhere and smuggled in and assembled in a lab of nearly arbitrary quality if a hostile nation state was motivated. Perhaps $20k isn't enough but $20M is tiny for a government sponsored program and more than enough to cause catastrophic damage.
In any case, a fork of Bitcoin with bigger blocks has existed for years and the market doesn't prefer it despite all the big names and companies hyping it up at the time of the split.
Satoshi left Bitcoin so there wouldn't be an appeal to authority so maybe your argument isn't as strong as you think it is.