I've read that it forms an alloy with copper, slowly soaking into and discoloring it. It doesn't destroy it like it it does Aluminum, but soaking into the metal slowly does present a problem. Unless it's saturated, or they use a special metal that doesn't form an alloy, it'll "dry" out. Also, all liquids evaporate well below their boiling point! Even metals. Mercury evaporates into the air at room temp, for example. So, even if they prevent it from forming any alloy it'll still slowly evaporate. At least it's easy to replace, or so they made it seem in the tear down.
Yasuhiro Ootori didn't really address this except to say that the 'decision was necessary cool the APU, given it's high thermal density' and that they spent "over 2 years adotping this liquid metal cooling mechanism". He did use marketing buzz words like "long-term, stable, high cooling performance." However, unless they tested the APU with liquid metal for 2 years under load, which they couldn't do because the technology hasn't existed that long, alpha/beta hardware design changes in the manufacturing process prevent you from having finalized hardware for long term testing, and other logistical constraints. In short, they don't know for sure! These claims are always based on simulations, computer and real world test benches. An accelerated quality assurance load wouldn't work, as time is an inextricable factor in the evaporation rate of Liquid metal. So, there's no way they can properly simulate this. Only time will tell. Just like the PS3 and PS4.
What really has me worried is that the temperature density of the APU "required" them to use liquid metal! That means that this thing will place a serious stress on the FCBGA and bumps of the SoC. If and when the TIC becomes less effective, or the heatsink gets clogged with dust, BGA defects can occur even quicker than they did for PS3/PS4. FCBGA is just bad technology and needs to be abandoned! Hot chips in video game consoles is inherently going to limit their lifespan. Unless console manufacturers maintain backwards compatibility or forward port their game libraries, the modern era of gaming is doomed to never become retro. That's because the consoles that can play these games will not last long enough for the games to become retro. Unless new hardware is made to play theses games, or emulation can keep up then all the hardware capable of playing these games will be e-waste.
No problem, you say? "The games can be downloaded! So when the PS6 come out, you can just DL your PS5 games." You're assuming the PS6 will be backwards compatible, that SONY doesn't de-list your games, and that there will even be a PS6 at all. Maybe they go all subscription, like Valve. Playstation Plus and XBOX Game Pass is all you need on whatever device you have that's fast enough to work. SONY and Microsoft will be out of the hardware business and in the subscription business. Then you games rely on you paying in perpetuity to play. You own nothing, just how they like it. That's the future of gaming!
Meanwhile NINTENDO is sitting back with it's cool running low TDP consoles that don't generally have overheating problems; they're laughing all the way to the bank while MS and SONY beat each other to death and loose consumer confidence in their overpriced hardware. "If I want PC gaming performance, I'd upgrade my PC." For the price they charge you can get a graphic card that'd beat a PS5 anyway. The days of consoles outperforming PC's in purpose built applications is long gone. The SSD tech isn't that impressive and PC's will not lag behind it long enough to pay the early adopters tax.
Nintendo took a different strategy altogether and I'm inclined to agree that staying away from high TDP at the cost of performance is the wiser move. Portability, strong characters, and great games is sufficient to weather the storm. Once MS and SONY have converted all their followers to the subscription service fever dream, Nintendo if free to continue gouging it's fan base with locked down hardware, overpriced games, toys, collectables, and anti consumer tactics. Namely, artificial scarcity to justify never lowering prices. Business as usual, but without competition in the console market.
Rant over.
I need the nice big handle to avoid slipping. Half of them go straight in to the trash, though, since like you said they're too sharp or too thick. I don't like trying to sand them, once that crappy metal starts to get roughed up, it seems to try to resharpen itself constantly. I use one of the long thin ones to cut the CPU silicone, then I use one of the short fat ones to protect the substrate when I jam a screwdriver in to pry off the GPU IHS.