For me the price is ok and bought it despite having v1 for 2 years. Especially universal license is a huge deal comparing to the previous licenses. With v1 I gave up on mac licenses buying only windows ones because I didn't want to pay double for the same software. Now with a price of more-less two applications I got not only variants for 3 OSes but also Publisher as an extra.
Referring to price raise - it's nothing weird, having 6-years inflation and especially actual state of world's economy in mind. Even JetBrains decided to raise them.
However I saw few times companies announcements after unexpected (from users' perspective) paid new version release that they are ready to give refunds or bigger discounts for users that bought previous version in eg. last 6 months. Serif would make happy some reasonably annoyed people with such move. But as I said - I saw that few times while eg. as @PaulEC mentioned, there are also situations with quite opposite approach.
In the end whatever Serif does, I personally won't judge as I'm on neutral ground with this - just giving some ideas in this topic.