Bitcoin cannot scale, until the fixed blocksize issue is fixed.
There is no fixed block size issue because by most people's estimations, something like the relay network is required for over 500k-ish blocks. Because there is currently no alternative to the relay network that isn't opt-in, this just makes it a cartel creation type of tool to exclude various adversaries from interacting with the network at all.
What do you expect, Monero is just gonna scale to 100mb blocks with no side effects? Monero does not solve Bitcoin scalability issues. There really is no huge scalability problem in the first place. I estimate around 8MB blocks is what is needed to have $10kish transactions and higher valid for on-chain use as a major world currency. That's just within capability of catching mainstream consumer support.
But the difference is that Monero doesn't artificially limit the scale for either political (is it a coffee chain or a remittance network?) or structural reasons (hard block limit needed for fees with a limited emission). The Monero code allows the system to grow "organically" with the technology.
Imagine - 5 years from now - Some whizzbang scientist finds a way to increase the bandwidth of the internet 100 fold within the existing architecture, and samsung has just released 5-dimensional SSDs that read/write at 5 TB / second.
Do you know which network would automatically scale to exist within this new hypernet? Monero.