When I moved back to Portugal about 4 years ago, I actually pondered on going to Germany instead, and actually went and lived in Berlin for a while and investigated and compared costs of living.
Back then rents were already higher in Lisbon than Berlin (whilst salaries in the former are less than 1/3 those in the latter!!!) and the only thing that made living in Lisbon cheaper was that Portugal has a National Health Service (free to use) whilst residence in Germany means mandatory Health Insurance which for me - who have my own company - meant an extra €300+ a month in costs.
In the last 4 years housing costs in Lisbon went up by almost 50% and in Berlin it was 10% or so (if I remember correctly), so now it’s actually significantly cheaper to live in Berlin, which is a way better place than present day Lisbon to live in pretty much every way but Weather.
I’m actually living in a small city about 200km from Lisbon were I pay less than €400 a month for a one bedroom in rent, so it’s not bad for me, but that’s because I’m not having to live on the average portuguese income and don’t have to raise a family.
Living in Lisbon would be crazy and I would be better of moving to a more cosmopolitan place like Berlin (especially because, having lived in Amsterdam, London and Berlin, for me Lisbon just feels like a pretty provincial city, hilariously filled with people who don’t know best and by comparing themselves with the countryside think they’re sophisticated and forward thinking).