the thing you dont realise is.. bitcoin is a PUBLIC ledger, you have no right to privacy in PUBLIC
if you want privacy you have to create that privacy for yourself away from the PUBLIC
(this common sense notion applies to many things in the real world)
bitcoins whole security model is to be able to publicly audit every transactions provenance right the way back to its coin creation origins.. this provenance chain of custody of value that coins transfer to, from one address to the next is defined as having a taint of X based on certain things of its history
and a utxo's 'taint' is rated as a scale and can go from white(clean) gray(suspicious) dark(dirty)
taint is not a verbage to say its dirty by default.. as taint is not a yes/no thing.
the reason financial monitoring analyst services do actually analyse and tag utxos with a taint of x is because bitcoin became defined by law as currency around 2014-ish
which then caused financial jurisdictions of financial laws to then apply to bitcoin also
so the consequence of those lobbying for "mainstream recognition" ended up with the financial laws having jurisdiction
yes before 2014 bitcoin was defined as private property and there was not much financial analysts could legally do (could not demand services to disclose personal information on customers that used bitcoin)
but things have changed negatively in regards to how governments are involved in bitcoin and how they delegate money service businesses to monitor customers deposits and withdrawal history and share info between each other, by law.
if you dont want services monitoring your stash as much and you dont want them tagging your stash, you are probably better off avoiding using mixers that services get triggered by. and instead learn all the triggers(from source info or regulations, not bloggers emotional rants) and then avoid the triggers and then you can just hide in public amongst the masses of other transactions.. (vanish into the crowd)
in short. taint is a thing and its actually worth you knowing the triggers of what makes financial services tag certain utxo's with a taint rating, and how to lower your utxos rating to avoid services from noticing you and sharing information they have about you
its not just depth..
if you think it fizzles out after (random number) 10 child transaction depths, you also have to be aware that the depth only fizzles out if that depth is separated by X time
its the same as fiat. doing 1 payment of $9,900 a year doesnt trigger any reporting. so you can do it for 10 years(10 times) and it not be a big deal
however do it 10 times within x months.. and they will treat that 10 actions as one action of spending more then $10k over a period, and report it as such
so when hopping value over 100 addresses in a short period of time, even if its way more than 10 times within that short time. they treat it as one act of TUMBLING and tag the destination funds as same owner as the origin funds 100+ parent transactions ago
in short..
spamming the blockchain with address hopping. ends up being called tumbling which gets you highlighted as a red flag, and tagged as the funds 100+ tx ago being same owner as latest.. thus defeating the point of address hopping