Yes, NVDA is stopped out & will be removed from the Active Trades category as soon as I post an update on the front page. I just wrapped up a video in which I covered NVDA along with the semiconductor sector. Video is processing & uploading now.

A beta-adjustment of 0.90 would mean 90% of a typical position size, i.e- a downward adjustment of 10% in order to account for the elevated volatility expected in NVDA.
Using a computer (instead of a mobile device), if you hover your cursor over the phrase ‘suggest beta-adjustment’, or any term on the site with a dotted line below it, the definition of that term should pop up. A more detailed explanation of beta adjusted position sizing can be found on the FAQ page under the Trading Related Questions sub-category.

Yes. At minimum, I expect another move back down to my first target on GBTC around 514 & still think there is a good chance that it will continue down to the second target around 301. If/when that bubble finally bursts, there will likely be much more downside so if you were or are able to find some shares to short & want to tuck them away with the appropriate stops in place, the 150 area looks like a nice longer-term downside target (about a 77% drop from current levels).

Most likely. I was going to short GBTC today & add it as an official trade idea but Interactive Brokers doesn’t have any shares available to short. As IB has the best availability of HTB (hard-to-borrow) shares, if they don’t have any, chances are that most if not all other brokers don’t have any shares available to short either.
GBTC just backtested the bearish rising wedge that I posted a few times recently (daily time frame). Price are now moving lower following that backtest & I suspect they will continue to fall from here. My point being that if Bitcoin prices fall, so will the GPU makers (NVDA & AMD) as the demand for graphics cards to mine Bitcoin & other cybercurrencies will fall as well.