Will solid-state lasers gradually be replaced by fiber lasers?

This is quite challenging. To summarize briefly: 
1. Fiber lasers inherently generate higher noise levels than solid-state lasers.
2. Fiber structures have limited energy tolerance. Pure fiber configurations struggle to achieve hundreds of watts of power as effortlessly as YAG crystals. 
3. To amplify fiber lasers, spatial optical paths are still required; fiber-based amplification is highly challenging. 

Fiber lasers can be made extremely compact—with proper engineering, the entire laser plus power supply can be miniaturized to the size of a trade show badge. However, their wavelength options are limited due to the physical constraints of the gain medium. Currently, commercially mature fiber lasers predominantly operate at fundamental wavelengths of 1030nm or 1550nm. While 920nm is available domestically, it lacks the maturity seen internationally. Blue, orange, and plasma laser wavelengths remain beyond the current capabilities of fiber lasers.

Considering the distinct characteristics of fiber lasers and solid-state lasers, each type possesses its own irreplaceable upper limits and unavoidable shortcomings. Therefore, debating which will replace the other is meaningless; it merely reflects differing perceptions across various application domains and eras.