but 1 Bitcoin is always equal to 1 Bitcoin. If someone tries to convince you otherwise, do not buy from him, as he is scammer.
but.. if i moved my hoard.. no one bats an eyelid
if someone moved their 2009 mined coins.. it provokes a reaction
people do look at each coin differently
heck fiat is like this
if you get money at christmas from a relative the authorities do not care
if you get money from a drug dealer. the authorities do care
$10k from an employer is treated differently than $10k from relative, vs $10k from pension, vs $10k from selling a product vs $10k crossing a border
in bitcoin a fresh mined btc is differently than a blacklisted btc that was on silkroad and then went through a mixer. authorities do watch for these
if 1btc=1btc then mixers would be redundant and not used.. so why so much advertisements that mixers are needed
funnily enough i find those promoting mixers as scammers. wanting to lose their dirty coins onto innocent people they scam by saying all coins are the same to scam innocent people into giving away clean coins to someone handing them dirty coins
end result is innocent people told btc=btc get fooled into swapping, thinking there is no harm. but end up holding dirty coin and end up getting questioned and investigated if they use their now collected dirty coin with a service that watches for dirty taint
in short if someone says 2 statements together. they are deceptive
a. btc=btc (meaning mixers are not required as all coins are equal)
b. promote a mixer service and say even/especially innocent people should use it