The introduction of Segregated Witness (SegWit) which was proposed in BIP-148, allows block capacity to be indirectly increased thereby removing signature from Bitcoin transaction data.
You fell into somewhat common misconception. Block capacity increase realized due to change on how transaction size is calculated. Block still contain transaction along with it's signature data. It's only removed when a node (which support segwit) send block/TX data to a node (which doesn't support segwit).
For every SegWit address, it can begin with bc1 or 3, but it main purpose is to offer lower tx fees by taking up less block space. Even with this implementation, we haven't been able to say "Goodbye" to congestion.
SegWit main goal is to solve transaction malleability.
1. What do you think is a possible solution to this problem?.
I've seen some people focus on single approach (such as only focus on LN or only focus on block size increase). But IMO we should accept various method to mitigate the problem, such as making
OP_FALSE OP_IF ... OP_ENDIF non-standard, increase block size, use LN/sidechain (if it match how you use Bitcoin) altogether.
The debate about increasing the block space has been raised multiple times in the Bitcoin community but it has been rejected because it will lead to the centralization of miners which is completely against the idea of Bitcoin's existence.
Your statement isn't that relevant with today's condition though.
1. Miner usually join mining pool.
2. Mining pool can afford decent server and internet to run full node.
3. Compact block help improving block propagation.