We have been told repeatedly about the dangers of WiFi. Yet it is pushed on us relentlessly, while fiber optics for signal transmission, especially in the United States, is slow to be utilized. Is use of fiber optics safe? Are there potentially safe implementations of more localized WiFi (like Bluetooth), while the primary conveyance can be done more safely with fiber optics rather than 5G and microwaves? If so, then why is this not being aggressively pursued?

What you have described here is literally true and correct. The use of fiber optic transmission of digital messages is safe compared to beaming them through the air. With a fiber optic cable system, the energy is confined to those cables and connectors, and is not polluting the environment like the electronic signals that are omnipresent in almost every space, and soon will be all-encompassing with the full rollout of 5G or other advanced WiFi technologies from the use of low orbital satellite networks that literally cover the globe and beam unhealthy radiation at you 24/7. It is far safer to use a Bluetooth device than to hold a cell phone to your ear because you are farther away from the microwave radiation that is being emanated. But it is better to use a wired headphone of some kind that does not rely on a WiFi signal of any sort; there is little danger from the direct current flowing through a headphone cord. So all of these technologies are produced and promoted with no thought to safety on the part of the designers and manufacturers, for the most part, nor are regulatory agencies stepping up and taking appropriate action to consider safety when there is actually mounting scientific evidence of the harm from microwaves, things involving both cell phones and the WiFi signals that are worsened in the newer generation 5G architecture. There are, in fact, devastating consequences that are ever-present and growing. By the time human society figures this out, it will be too late to save the many thousands dead from cancers and other maladies they cause. As your question points out, there are already effective technologies to allow digital communications transmitted safely. The fact that is not being done is entirely sinister. Without suppression through mind control, safety would have been considered from the outset, looked into carefully, and then been part of a global decision to constrain and confine the electronic components within a physical network, such as a fiber optic cable system rather than beam it everywhere in the environment.