Rails had its time and there were reasons why people liked it. But when I see that people post that Rails is still great in 2019, I'd like to stress following issue because those people might confuse newcomers who have to decide which ecosystem they gonna join.
The problem is that being in a big or biggest and still growing ecosystem makes life much easier. Once an ecosystem is on the decline you get less good libs or libs are not actively maintained anymore and the best people who shape tech are also moving to new ecosystems. I don't want to bash Rails but just an example, I didn't see any proper http/2 support in Rails-land. Now, you could say who needs http/2 (it makes a huge difference btw). But the point is that it arrived in one of the biggest ecosystem just recently and not every lib there supports it out of the box. And that's just one of many examples. People repeat that Rails has so mature 'gems' but I don't see a lot of new stuff or a big variety, tech moved on but without Rails. Just accept it.
The real problem behind all these discussions and threads. Imagine there was a time, where Rails-guys were rare and Rails was the biggest thing. I had to pay such guys $200,000/yr (8yrs ago and not in the valley), not because they were outstanding. Actually, there were average, they were ok in Rails but missed a lot of other checkboxes (often devops or SQL). But the market demand forced us to pay such salaries. Rails brought them a good life and imagine demand was declining, so they had to get into other tech, start again at zero or smaller salaries OR went to forums and rant/try to convince people why Rails is so great.