Arbitrary limits are bad
Arbitrary boundaries are rarely a good thing. I'm sure there is a limit somewhere (maybe 256 tabs?), But as long as it's far from normal use, most users never know it and the treat as "infinite", which makes it a better user experience.
Having to manage "only 4" or "only 8" or a similar number of documents is very restrictive for the user. For example, classic WordPerfect 5.1 allowed easy simultaneous access to 2 documents. Do you want 3? No chance. Current word processors – no obvious set limit for the user.
The same problem arises in different places:
- Maximum number of rows or columns in a spreadsheet
- Maximum size of a free form text field (it is always better to make it so large that the typical user know there is a limit)
- Maximum number of simultaneous programs running in an operating system – unfortunately, we are experiencing serious memory problems and other unavoidable resources – but the general idea is not to impose arbitrary limits.
And then we come to who actually uses as many tabs in a browser:
Obviously, power users do it. Open news, weather, Google, StackExchange, the company's database, as well as several tabs job.
Casual users + bad website design