For those interested on that tax topic I’ve confirmed with Interactive Brokers how our data are treated in the scope of the CRS standard for information exchange between tax authorities. Although I myself had to implement CRS for some banks in the past years I indeed had a doubt looking at the generated CRS report available in the interactive brokers account where all relevant trades for a given year are listed and I thought they were the zealous kind providing more data than what’s required by the OECD.
For instance when one sells an option (short or to close an option position it does not matter) this triggers a CRS relevant event and I was afraid that they did it in a way that the whole list of trades would be sent but they confirmed that they only send aggregated data without any trade details and for the case of interest here that they basically do the sum of all sales proceeds during a year (i.e. option / stocks / etc.) and transmit that number alone without detailing the securities / product involved. The list of trades is just provided as a helper for you to check that the maths check (lol).
To summarize as long as you keep the option activity to a relatively small amount relative to your overall wealth there’s no reason for the tax authority to audit your trading activities. On the other hand of course if they are receiving information that you sold for 100k or securities in a given year while you only declared 10k of taxable wealth then I guess that would be a problem ^^. To that respect I guess that the general rule saying that you have to trade more than 5 times the amount of your assets to be considered a professional trader holds in that case.