maybe your not seeing the big picture because the numbers are so huge..
(i hate writing long numbers so ill simplify demo(dumb down) the numbers)
call 128bit.. 13bit (8192 combination possibilities)
call 160bit.. 16bit (65536 combination possibilities)
call sha256 .. 26bit (67108864 combination possibilities)
(now that you have corrected the/your preference)
if you are going to go through all
brute(0 to26bit)->ecdsa26->ripemd16(26bit)=p2pkh(16bit)
0 to 67108864 -> ecsda ->ripemd(67108864) = 67108864results of 65536(16bit combinations) (1024 collisions)
you will find your 67108864 results are actually ~65536(16bit) results listed repeatedly 1024 times
(in simple example collisions)
and then out of your list of lots of repeated collisions 67108864
you then have to compare the UTXO p2pkh to your big list to then look at the privkey to then spend it
you may think. great you have 1024 possible privkeys that can sign that same utxo
but reality is you wasted like 1000x time by bruting such a big number
..
however if everyone uses seeds of 13bit randomiser to make privkey
128bit (12seedwords of 2048 librarywords)
you follow the complete process which everyone else follows.. meaning less brute attempts needed
because: everyones seed based private key is somewhere between0-8192(13bit) because they all using 13bit
do you get it yet? everyones seed in this demo is between 0 and 8192. and there are only 8192 resulting p2pkh that match the privkey/seed out of 65536 possible keys
and before you ask.. no.
just bruting0-8192-ecdsa-ripemd will give you 8192(skipping sha).
but you missed the sha 'scatter'.. meaning your results 8192 p2pk might have only 1 p2pkh that goes back to a range within the 13bit seed
however doing it the full way
only need to do brute(0 to 8192)-sha->ecdsa->ripemd= 8192
and then you will have all the keys that people use seeds would ever end up using
no long lists of unused keys that are out of bounds of the rule.
no extra cycles. no end results that dont lead back to a 13bit possible seed
emphasis:
less brute cycles. less end results. but all results in range of all users range of their own key gens
thus less to sort through to compare to the utxoset too
(outside the demo in real bit number terms)
its still a huge number. meaning still a project you have to hand down to your offspring and descendants to be bruting on their colony planet in millions of years
but can be completed a few millenia sooner