I think that depends on how you scope the bounds of "systemic" as opposed to "institutional" as opposed to something else, and also what degree of impact you demand before you call it "racism".

(1) If an industrial area was zoned close to a neighborhood with a lot of black residents as opposed to one with a lot of white residents despite similar economic considerations, specifically because the planning board in the 1950s who set it up was explicitly racist, and everyone on that board is now dead, there's still likely a disparate racial impact. This is "institutional" or "structural" racism, but is it also "systemic"? This kind of thing is widespread (though the degree is often exaggerated).

(2) There is some evidence that people prefer others whose physical appearance is reminiscent of their own (one aspect of homophily). Race is usually a readily apparent aspect of physical appearance. Is this preference racism? If we declare that racial homophily is not, on its own, racism, but we publicize negative events in a racially equitable way, then everyone is exposed to the impression that "there aren't many of X but they do a lot of bad things"--is correctly assessing the relative frequency of personal contacts across various groups and accounts of malfeasance in members of those groups "racism"? (Is it classism if you do it with people of different economic classes?) (Note: these frequency-estimation effects have been observed in the human populations, where people mis-estimate how many people there are of different groups because they over-weight their own network which is homophilic rather than random--https://pubmed.ncbi.nlm.nih.gov/31406337/)

So I agree that there are cases where clearly individuals are racist, and there are systemic problems because of this: individual racism drives systemic racism.

But it's also not entirely clear to me that it is impossible to have states of affairs where you would never charge individual racism but you still would conclude that there is systemic racism. To me, this seems like an open question. (Continuing to address individual racism seems pragmatically like the best approach initially, and "then we'll see", if we can manage to turn things around from the present trend of encouraging everyone (via different mechanisms) to be more racially bigoted in the name of anti-racism.)