There are proactive ways to Stop any conflict or situation (war) one found himself. Boycotting Russian's own Gambling company might not be the best way to Stop the war. It will only affects the Nation's GDP, but remember other Countries will support Russian to Sustain during the war. If you boycott these companies, what of those people that have invested a lot.
Although it is a war tactics, but innocent people suffered the more.
The best ways to stop war are:
1. Set up a committee for the both sides of the war plus a neutral committee
2. Call the two parties for a dialogue
3. Settle the immediate and remote causes of the war.
With these I believe war can be called to a resolution stage.
Do you think UN, NATO and other group don't resort to a peace talk before imposing those multiple sanctions to Russia? Ukraine President even have a several peace talk with Putin during the war yet Russian force never stop on there aggression. So tell me, If Russia have unlimited support from other country, why they are now doing desperate move just to sell there oil on there allied country if they will really have that backup.
There reaction against economic sanctions only proves how it was effective. Russian oligarchs fund this war so cutting down the financial souce will gonna hurt there military spending.