My position is as follows:

-LFP wins on price where it fits the use case, so grid storage, current-gen EVs.

-Silicon anode competes for market share with solid-state in areas where LFP can't, namely aerospace and next-gen EVs or even aviation, should they ever reach 1kWh/kg. The former has easily a decade lead considering that they're already selling packs and the latter exists largely in the lab or on paper.

I also believe even 400Wh/kg at pack level is already good enough to be a serious proposition as replacement for internal combustion in land transportation, provided pricing is adequate.

I totally agree with your position on LFP, and about 400 Wh/kg being enough to unlock some applications.

But I’m not fully convinced on silicon anodes versus solid state. Yes, energy density is very promising, but I understand capacity fade is still a huge problem due to silicon volume expansion/reduction while charging/discharging?

That's the problem they've solved here using nanowires - the cells have a 200-1200 cycle life depending on operating conditions - I suppose the range is so wide because of the temperature range - -30°C - 55°C. It's not surprising to see cells degrade fast at the hotter end of this spectrum.

For EVs they advertise cells with no less than 410Wh/L, 4C rate of discharge.

Is there still a fire risk with LFP? From my understanding, solid state batteries have a large safety advantage here because of this.

Yes - LFP still uses a flammable, liquid electrolyte - usually ethylene carbonate.

That being said LFP survives the nail penetration test without causing a fire, so it's considerably safer than the usual alternatives.

LFP cathodes and silicon or 'solid state' aka lithium metal anodes are not incompatible.