Do you cleanse your house after practicing magick/craft?
Nope, never even considered it. The only time I do a "cleansing" of my entire house is when I need to banish unwanted energies or as part of a usual "cleansing" thing at the appropriate time of year (MidWinter, in my tradition).
For clarity, I'm putting "cleansing" in quotes because the meaning of it in my tradition seems distinct enough from the OP's drift that it seems necessary. I'm aware that in other traditions, cleansing is seen as some sort of standard practice. The term "cleansing" gets applied to anything from generic (but ritually-intentioned) house cleaning to dedication rites and preparation of sacred spaces, among other things. In my tradition it's a specific subtype of restoration whereby unwanted influences are removed to restore the original state of something.
For an animist, this means there are fairly significant ethical considerations. Doing cleansing on another person is potentially a violation of their nature and agency, so cleansing is typically only done on oneself. Occasionally, it may be done with persons one has a meaningful relationship with, like Spirits of the Home. Then, doing a clean every so often (literally and/or metaphysically) is a show of devotion and respect. Non-animists will not share this perspective on the art of cleansing, though, so ignore as pertains to your worldview.
Are there people who choose not to cleanse their house afterwards, and what are the results?
Me, I guess? Couldn't tell you the results as I have no basis for comparison, but it's never been a problem.