That is correct a Lightning Node is a different system, it should warn you it is experimental when launching Lightning Node app for the first time and not to store significant funds…
You can find a guide here explaining and it is a nuanced topic to run liquidity for your lightning wallets so will require a bit of DYORing,
As it breaks it down you can connect a Bitcoin wallet to your Bitcoin node for onchain, Lightning is offchain and has different backup-recovery methods for creating offchain liquidity you can connect your lightning wallet to… Not sure how to more easily say that open to suggestions
I’m sorry you had an issue, what OS did you reinstall, let me know if you still needed any assistance
for the second statement I’m personally speculating but the developer that raised the issue I think the fixes were already being addressed by the community as early as February with no funds confirmed to yet be stolen this way with the HTLC replacements so not sure why indeed like he said it had taken a while, and seems to be a bit of FUD sensationalized now- the beauty of lightning! AFAIK there are still several enterprise nodes with hundreds of BTC that will keep updating to the latest versions!
Let me know if you have any questions or feel free to hop in Telegram/ping if needed help setting up at all! Happy to chat!