Have you ever noticed how quiet the HF bands are after a major contest? It was true last week after CQ WW CW and it is true again this week after the less popular ARRL 160 meter contest. This is quite different from what I remember decades ago.
Contesters were a minority back then. There was a lot of conflict on the bands during major contests due to the abundance of conversations, DX hunting, nets and so forth. The HF bands are quieter now. There are several reasons for the change. Since I've discussed this before (as have many others!) I won't repeat them.
Despite the lower level of HF activity, why are the bands unusually quiet on the Monday morning after the contest? The reason appears to be that a large fraction of today's daily activity is by contesters. They (we) are resting.
Immediately following a contest that I have little interest in turning on the radio. There is fatigue, chores delayed and an aversion to returning to the air so soon. I am not alone. Unless there's an interesting DXpedition, a 6 meter opening or something else sufficiently attractive to draw me back, the radio stays off. About all I might do is to monitor DX spots for items of interest.
On Sunday evening after the ARRL 160 meter contest, the lack of DX spotting activity was notable. I recall one period of 30 minutes when there were just a few spots from stations in the eastern part of North America (I usually filter spots from elsewhere). Flipping from band to band showed a blank band map. Tuning the CW segments uncovered nearly no signals at all.
Activity will soon recover as the contesters rest and recharge. We don't stay away for long. There is no need to suspect an elevated geomagnetic activity level since that does not hurt conditions enough to keep the enthusiasts away. We really have become a hobby where radiosport is a top interest and motivator.
Of course there are many exceptions, but that does not detract from the point. Digital activity continues, though even that is at a lower level. Those normally absent from the HF bands, such as VHF aficionados and those strictly on FM, likely don't notice. Tinkerers and makers might similarly be unaware. Hams active in SOTA and POTA also seem not to notice, although they may enjoy the brief respite from QRM. Yet it is a phenomenon.
Is it a problem? Probably not, at least not yet. What it may suggest, however, is that unless radiosport is taken up in a big way by new and younger hams the HF bands will only become more silent in the future. This is already happening to a degree, but a full generational replacement is unlikely.
While it is a sad development for many of us, the amateur radio hobby will continue to change in the direction set by trends in technology and culture. HF will likely play a lesser role in that future.