I was always fascinated with lighting, so of course I was one of the first to use CFL when they came out. They were a pain, clunky, and worse, they would have to warm up if it was a bit cold. The cold cathode CFL appeared, and they were great, simplier, longer life, and very little warm-up. They never were very popular, but I still have some and they still work.
LED bulbs had a similar journey. When they came out, they were designed with a large power supply in the base and just a few big blue LEDs that turn to white light using a yellow phosphor. Most bulbs today still use such a design, and dimmer and flickering have become a constant issue. You had a current driven LED being powered with an AC pulsed power supply, and results weren't always great.
In my opinion, the greatest LED bulb invention was when AXP Technologies invented the filament LED bulb. The power supply was mini, and many small LEDs (red and blue) were built on a glass substrate and covered with a glass phosphor coating. Most of their bulbs are Energy Star and UL certified. A "60 Watt" AXP bulb uses 7 watts where a "60 watt" Cree of Philips bulb uses 9 or 11 watts. That can add up. Also, since their power supplies are so simple, they usually dim well, but your mileage may vary.
Today many companies have copied the AXP filament bulbs, especially the Chinese, so do be careful with the "cloans." Today almost all LED bulbs in my house are these filament bulbs, and I love them. They are lighter, the most energy efficient, and smaller for their brightness. They are up there on life, because most regular LED bulbs fail not due to the LEDs but due to their cheap power supply. The filament bulbs have a very simple power supply, so in my experience, they last pretty long.