Apologies, missed that question.

Why now?

My response is:

If not now, then when? the next halving is approaching fast and likely means (no guarantees of course) more new people will be joining the btc network. As more people join the network more noise will be communicated and less signal. Making it even more difficult to implement changes in the future in that scenario.

And side chains dont just magically fix everything overnight. They need devs and users to grow organically to see what works and doesnt work. Could take a some years for a sidechain to get adopted via organic growth. Rootstock, Lightning, and Liquid have still very low adoption considering their time in the market.