Here are Twitter financials for the last year.

Revenue $5,078 (in millions)

Cost of Revenue $1,798 35.40%

Sales and Admin $1,760 34.67%

R&D $1,247 24.55%

Interest $52 1.02%

Unusual Items $441 8.69%

Their biggest expense 34.40% is "Cost of Revenue" followed by "Sales and Admin". For a company like twitter "Cost of Revenue" includes operations and Customer Care.

I don't think that they can cut 75% at once, just the severance payment will be huge and they may not have the money for that.

With R&D being only 24% it is possible to make large cuts in "Cost of Revenue" and "Sales and Admin" and keep more of the engineering team.