Conservatively not if you are looking for a stable path but optimistically yes if you are ready for the adventurous ride and be curious always with new changing things. If you think learning one software and that can help you life long, 100% digital marketing may not be suitable. Search engines, social media, user behaviour.. All these things keep changing, so you need to change to fit the environment.
Like in a supermarket, where the shopkeeper monitor the demand and supply of their products. You need to watch the digital industry trend (demand and supply in the skillset). Linkedin yearly report would be good enough to monitor this. Or else you could check the number of startup job listings in Angel.co and linkedin for jobs which are bigger than small startup. Or your regional job boards and niche sites.
In fact, career in digital marketing and analytics was most in demand on last few years. One perfect proof is the survey released by linkedin about the skills in demand on 2018. But 2019 the trend is changing as well because of the steady increase in digital marketing people supply. One significant example I would like to share is the Singapore government took the initiative to coach their citizens the digital marketing skills. Even my colleague who is a designer went to get free SEO training from Govt sponsored skills training.
A google trend
According to Linkedin, 2019 most Skills in demand
source: career in marketing