But as high-power transistors were developed, SCRs fell out of favor. In particular, once an SCR is turned on, it stays on until power is removed or reversed; this makes SCRs harder to use than transistors.
SCRs, also known as thyristors, are still widely used in very high power applications.
Thyristors in the strict sense of the word, i.e. SCRs, are still used only in a very small fraction of the applications that were dominated by them a few decades ago.
Classic thyristors are useful only for controlling 50/60 Hz AC consumers.
Many applications that were done in the past with normal thyristors, for lack of alternatives, like electric motor control, are done now with GTO (gate turn-off) thyristors or with IGBTs (insulated gate bipolar transistors) or with silicon carbide transistors.
Even the use of GTO thyristors is regressing. If any thyristors will still be used in the future, they will use silicon carbide, with which they can be much faster than the silicon thyristors.
SCRs, also known as thyristors, are still widely used in very high power applications.