Ask HN: Should I learn Ruby for job hunt

I'm currently in a non-engineer role, but I use Python as a hobby. In fact, I have appeared in conferences to explain about the inner workings of Python. Because I don't get to apply my technical knowledge at my current job, I'm thinking of moving to an engineering role at a B2C company. Here in Japan, most Python roles are limited to Data Science, a discipline that requires additional training. I can't find a lot of Python web dev roles (or companies using Django).

Meanwhile, Ruby is popular here in Japan, so there are more Ruby web dev positions. Rails seems to be still hot here. I'm thinking of learning Ruby to be more employable at this companies.

When I asked a Japanese forum about this, I got these reactions:

[Learn Ruby]

- Many more web dev jobs in Ruby than Python

- Many startups will keep using Ruby in the near future

- Rails provides a suite of features

- Decent Ruby ecosystem in Japan

[Don't Learn Ruby]

- Ruby is sunsetting

- Ruby is resource-intensive

[Alternatives from nay-sayers]

- Find a Django job

- Learn Go

****

I have these questions:

[Ruby knowledge prior to applying]

1a) How much Ruby would I have to know to apply for these positions?

1b) If so, how much time do you need to be proficient enough with Ruby and be employable?

[Rails knowledge prior to applying]

2a) Do you also need to know Rails?

2b) If so, how much time does it take to be proficient enough with Rails and be employable?

[Alternatives to Python]

3) Are there any other programming languages that is (i) easy to transition from Python and (ii) has many web dev jobs?