If you're already familiar with how scarce sources are for much of Bactria's history, particularly in ancient periods, then I won't retread that, except to say that the situation has been improving across the past 70 years through excavations and the occasional discovery of additional textual material, so there is a reasonable hope that things will continue to get less scanty as time goes on.

Fortifications built across commanding high points are absolutely a common feature of this region in most pre-modern periods, so it's definitely a plausible read of visible tells and man-made features in the landscape as a general rule, and the aridity of much of the landscape does make a lot of archaeological features stand out even to the level to which Google Maps can go, let alone anything higher res. My one note of general caution (as opposed to a specific reaction to any of the spots you highlighted) is that some tells have a more visible scale or shape than others, and there are possibilities other than forts or citadels for visible features in the Bactrian landscape, such as temples, walled villages/towns, or prehistoric features. Indeed, the growing realisation that Bactria (and surrounding regions) had a highly urbanised existence as far back as the Middle Bronze Age have really added to the sense at which current archaeology is just scraping the tip of an iceberg. There is a lot out there. That also makes it more difficult to tell an unexcavated site's potential dating from aerial photography where one lacks a super visible layout. In most cases these sort of stand-alone sites, where there isn't a modern city/town on top, tend to require actual excavation for secure dating and evidence.

What complicates the picture more is that, as with other parts of the world, many sites were re-used even if they ultimately are no longer occupied in the present day. If you're familiar with Ai Khanoum, the type site for Hellenistic era Bactria, that's a very clear example- it's most known as a Hellenistic era city site because that's the only era in which that site was a city at all. However, the fortified citadel that overlooks the city was re-used in the Samanid and Timurid periods, and there was Achaemenid-era usage of both citadel and what became the Hellenistic era city walls. Indeed, there's an Achaemenid era fortification a few km north of Ai Khanoum that doesn't seem to have been reoccupied even though it's really visible on the landscape. None of this would have been known without excavations in the area, and even if one era's 'presence' on a site had been identifiable from aerial photography or satellite imagery it wouldn't form a clear insight into that site's overall history of use, only which era left the most prominent mark on it.

When it comes to the sites you've marked, however, I have a nasty feeling there's a relatively recent and unpleasant explanation for them- their overall size is too small for an actual fort, and the landscape nearby is absolutely covered in these in a way that could never reflect a premodern fortification pattern, it's far too dense. Premodern fortified borders were not the Western Front. Given their dimensions, density, and placement, I'm almost certain these are all abandoned farmsteads/villages you've identified, and a lot of the fortification you're seeing is intended as low scale protection/boundary enclosing but also protection against sand-laden winds. That, if anything, is even more ambiguous period-wise than a fortification or large urban site, but my honest conclusion is that there's a strong chance these have been abandoned in the 20th century. Now, it's not impossible we're looking at sites that are older than that abandoned as a result of climate and the gradual shift towards urban concentration of populations, I can't say for sure these are definitely places abandoned as a result of the Afghan Civil War or any number of other major 20th century crises in the region. It just seems the likeliest explanation given the paucity of alternative urban settlement within a relatively short distance of most of these sites, as opposed to what I would otherwise expect which is some continued use of some of these sites and a relatively close by urban concentration. It's also not impossible that some of these have been abandoned in different periods, and it probably would be archaeologically valuable to excavate a number of these sites even if they were all abandoned in the same period, archaeology of the 19th and 20th centuries is a thing. But I don't think you're looking at fortified sites of the kind you're imagining in this particular case.