Calmac can, some days, have more than 500 sailings. Yesterday, there were 516 with only 6 cancellations.

The last serious accident, a sinking, was:

On the stormy night of 22 March 1973, on its way from South Uist to Oban, the Loch Seaforth struck rocks in Gunna Sound between the Isles of Tiree and Coll, with over 40 passengers and crew on board. All survived, without a single injury.

https://www.obantimes.co.uk/2023/03/16/the-ship-that-sank-an-island/#:~:text=The%20CalMac%20ferry%20MV%20Loch,in%20Gott%20Bay%20by%20Scarinish.

Globally, in the 21st Century alone, there have been around 40 incidents where ferries have sunk, often with the loss of many lives. Most have been in Africa and in South-east Asia but, 5 have been in affluent countries such as Italy and Canada.

In 2014, in South Korea a ferry with 476 passengers on board sank with no loss of life.

Also in 2014, an Italian ferry sank in the Adriatic with the loss of around 90.

In 2006, a Canadian ferry sank in Wright Sound with no loss of life.

In 2003, in the USA, the Staten Island ferry collided with a pier and 11 lives were lost.

In 2000, a Greek ferry sank with the loss of more than 500 lives.

None of the above services operate with a number of vessels and sailings anywhere comparable to CalMac.

Source: https://en.wikipedia.org/wiki/List_of_maritime_disasters_in_the_21st_century