As Giorno rightly pointed out, despite City's dominance the PL as a whole is still very competitive. Liverpool & Chelsea have just as much chance of winning the CL as City do.
City are very strong, they easily knocked out PSG, Dortmund etc. last year and they beat PSG again this year.
The comparisons to Bundesliga is just ridiculous. They only have Bayern and if Bayern were in the PL they would have to compete for the same pool of players as the rest of the top 6. They wouldn't be able to monopolize an entire market like they do in Germany.
In reality they would be forced to spend bucket loads of cash trying to keep up in the PL, their players would be ran into the ground in the winter fixtures and we know the Bayern hierarchy don't like spending huge amount of money, so in all likelihood they would seriously struggle.
Even if they spent a lot, there's no guarantee they would be able to compete for the title. We spent hundreds of millions and we're still trying to secure top 4. Man Utd have also spent an eye-watering amount of money and they're not any closer to challenging for the title.
To win the PL, teams need huge resources, plus strength in depth, plus a great manager to bring it all together. City have all that right now which is why they're so strong.