A railway strike in the central region of the Netherlands was announced for Thursday the 15th, which would have affected train traffic across the country, possibly including international trains. This would've been a problem for people travelling to Hivefest via Belgium, because of Covid-related entry rules for visitors from outside of the Schengen area.
However, @roelandp must have made some calls. The strikes have been called off for the time being, after NS, the national passenger train company, reached an agreement with the unions for a new contract. Union members might still reject it, but it's a serious deal, including a 9.25% raise in 18 months, plus two one-time bonuses of €1000, and a €14/hour minimum wage for all ages.
Source: NOS. See also the NL Times for a story in English. Dutch News isn't reporting this yet.
In any case, as a community we wouldn't leave people stranded. @minigunner was already preparing to pick people up by car, or even to rent a van if needed, and I could have helped too. Join the HiveFest7 Telegram group for urgent messages about such issues.
There are still strikes planned for regional public transport (mostly buses) on Friday the 16th. This will include local buses and trams in Utrecht, but not in Amsterdam, Rotterdam and The Hague, which have their own union contracts. Regional public transport includes some trains far away from Amsterdam, operated by other companies such as Arrriva, but this won't be a problem for Hivefest, unless a Dutch visitor is planning a long commute.
Economic background: obviously, employees want to be compensated for inflation, while railway personnel is complaining about a high workload due to staff shortages. At the same time, the pandemic was a bad time for the financial reserves of public transport companies. Passenger volumes haven't recovered yet.
NS isn't subsidized in normal times. It's a commercially operated state-owned enterprise, which pays for the right to use the train tracks and a concession to run intercity traffic. The busy core network is profitable, and so are the stations which it owns.
In general, I'm not seeing a lot of inflation-inspired strikes yet. The public transport sector is relatively formal. In some other sectors companies will be more likely to simply pay wages above union rates in order to attract applicants. On Tuesday the 20th, the government will present its budget for 2023. This event might attract some protests, but usually it's a celebration for fans of the monarchy. In case you're interested, note that Prinsjesdag will be in The Hague. We only pretend that Amsterdam is the capital of the Netherlands.