This is far too optimistic - just look at the "History" chart. The average age of 90s hashes when they were broken was 10-15 years. It's equally probable that the "modern" algorithms are just too young for us to see them broken.
There's some aspect you miss: For both major hash breakages there was a ~10 year warning phase (for md5 the first breakthrough was 1996, for sha1 2004), where it was basically clear these hashes were bad, just noone had done the full attack yet.
There's no such warning from any modern hash yet.
SHA-2 was originally published in 2001. The digest sizes are also much bigger. I don't think it's really 'equally probable'. There are even cryptographers who think it's not at all probable, ever.
