What this actually means is Scotland sometimes generated 200-300%+ of its demand from wind (and "exported" the rest), and sometimes low %age points and used other sources/imports. It makes it sound like Scotland is wind powered 97% of the time (only 3% more to go!), which is very different.
There is an increasing crisis in the UK of negative electricity prices (typically when it is sunny, windy and lower demand in the summer). Last year had more time than ever in negative, and the UK has another 10-20GW of commited offshore wind in construction.
Once this comes online, wind generation will often be over 100% of demand UK wide (right now it peaks over 50% regularly). There is approx 5GW of HVDC (with 1-2/GW a year more planned over the next while), but it won't be enough to export all of it outside the UK (and when it is windy here, it is likely to also be there, so they won't want it either).
This is going to end up with very negative prices for a lot of the time. Considering ~15% of UK supply is made up with nuclear, this is a real problem. You can't stop start nuclear like you can with gas.
So we are going to have to pay massive sums of money to wind producers to shut off production. And we are still going need masses of gas backup which is going to be used increasingly inefficiently to pick up the slack.
This may spur innovation in storage, but we are talking enormous quantities required in a very short period of time.