I advocate the exact opposite view: use what enables your team to be most productive right now. The popularity of frameworks may change three years down the line, and good engineers will be fine with that.
"Yeah, we're going to be another 2 months to launch because we're betting developers in 2018 prefer Go."
I'll be pretty surprised if you're still in business in three years.
The whole ecosystem is frankly a mess, you need to stay bleeding edge all the time to have a chance to long term maintenance and suffer any capricious api update each of your dependency might have because staying on old release and relying on backports is not worth it.
I'm not paid to clean other people libraries. If the idea of open source is that, then no thanks. Core business is not maintenance and costs like those do kill startups.
If you want to run on old software that you don't have to upgrade or maintain, you are going to pay for someone else to do it.
If you want your cake and to eat it too, you're unrealistic.
yeah, github is a perfect example or that, right? </irony>
Spoiler: the difference is, the new ones' bugs just aren't widely known yet.