Sorry, my bad, I should have written it more explicitly:
4KiB doesn't matter that much nowadays with regards to write amplification (read-modify-write cycles).
(i.e.: R-M-Ws will always happen upon in-place overwriting in a sub-part of an erase block).
Of course, it would matter to at least align the 4KiB block of an ext partitions with the 4KiB sectors, for read performance (faster to read a single sector that to reads 2 sectors and merge them).
(and given that the erase-block are a super-set of this sector layer, aligning to erase blocks to aleviate R-M-Ws will also get you aligned to sector boundary anyway).
4KiB doesn't matter that much nowadays with regards to write amplification (read-modify-write cycles).
(i.e.: R-M-Ws will always happen upon in-place overwriting in a sub-part of an erase block).
Of course, it would matter to at least align the 4KiB block of an ext partitions with the 4KiB sectors, for read performance (faster to read a single sector that to reads 2 sectors and merge them).
(and given that the erase-block are a super-set of this sector layer, aligning to erase blocks to aleviate R-M-Ws will also get you aligned to sector boundary anyway).